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61.
In this article I reflect on my teaching and scholarship with computers in secondary schools during the past 20 years. I chart how changing technology and changing expectations for technology shaped my teaching and student learning in the writing centers and classrooms where I have worked.  相似文献   
62.
We combined remote sensing and in-situ measurements to estimate evapotranspiration (ET) from riparian vegetation over large reaches of western U.S. rivers and ET by individual plant types. ET measured from nine flux towers (eddy covariance and Bowen ratio) established in plant communities dominated by five major plant types on the Middle Rio Grande, Upper San Pedro River, and Lower Colorado River was strongly correlated with Enhanced Vegetation Index (EVI) values from the Moderate Resolution Imaging Spectrometer (MODIS) sensor on the NASA Terra satellite. The inclusion of maximum daily air temperatures (Ta) measured at the tower sites further improved this relationship. Sixteen-day composite values of EVI and Ta were combined to predict ET across species and tower sites (r2 = 0.74); the regression equation was used to scale ET for 2000-2004 over large river reaches with Ta from meteorological stations. Measured and estimated ET values for these river segments were moderate when compared to historical, and often indirect, estimates and ranged from 851-874 mm yr− 1. ET of individual plant communities ranged more widely. Cottonwood (Populus spp.) and willow (Salix spp.) stands generally had the highest annual ET rates (1100-1300 mm yr− 1), while mesquite (Prosopis velutina) (400-1100 mm yr− 1) and saltcedar (Tamarix ramosissima) (300-1300 mm yr− 1) were intermediate, and giant sacaton (Sporobolus wrightii) (500-800 mm yr− 1) and arrowweed (Pluchea sericea) (300-700 mm yr− 1) were the lowest. ET rates estimated from the flux towers and by remote sensing in this study were much lower than values estimated for riparian water budgets using crop coefficient methods for the Middle Rio Grande and Lower Colorado River.  相似文献   
63.
Eye movement is the simplest and repetitive movement that enables humans to interact with the environment. The common daily activities, such as reading a book or watching television, involve this natural activity, which consists of rapidly shifting our gaze from one region to another. In clinical application, the identification of the main components of eye movement during visual exploration, such as fixations and saccades, is the objective of the analysis of eye movements: however, in patients affected by motor control disorder the identification of fixation is not banal. This work presents a new fixation identification algorithm based on the analysis of variance and covariance: the main idea was to use bivariate statistical analysis to compare variance over x and y to identify fixation. We describe the new algorithm, and we compare it with the common fixations algorithm based on dispersion. To demonstrate the performance of our approach, we tested the algorithm in a group of healthy subjects and patients affected by motor control disorder.  相似文献   
64.
Objective: To examine gender differences in the peer relations of children with congenital neurodevelopmental conditions (NDC). Participants: Thirty-four children with cerebral palsy or spina bifida and 41 typically developing (TD) children, ages 6-12. Measures: Personality Inventory for Children-Second Edition (PIC-2), Social Network Inventory for Children-Child Version, and the Friendship Quality Questionnaire-Revised (FQQ-R). Results: Children with NDC report smaller social networks and lower quality of friendships than TD peers. Group × Gender interaction effects were not significant. Conclusion: Prior to adolescence, the social differences and risks associated with NDC do not appear to be gender specific. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We describe an interactive gaze-contingent display (GCD) applied to clinical applications; the system uses a simple texture hole to inhibit peripheral vision, to test and stress overt mechanisms of visual searching in normal subjects. The correct use of GCD in vision research is affected by tremor of the hole, due to system noise, nystagmus, eye blinking, calibration and subject reactivity. These issues compromise the execution of task. In order to obtain a stable GCD hole, we implemented a predictive gaze-contingent display (PGCD), fitting through dispersion of fixations and modulating a filter. The paper describes the PGCD and compare it with the common technique, providing evidence that humans fit exploration based on the characteristics of the computer system; in particular we found significant difference applying PGCD or a simple finite impulse response filter. We suggest that a correct human–computer interaction applied to neuropsychological context must be developed taking in consideration both technical point of view and human behavior.  相似文献   
67.
Autonomy and Common Ground in Human-Robot Interaction: A Field Study   总被引:1,自引:0,他引:1  
The use of robots, especially autonomous mobile robots, to support work is expected to increase over the next few decades. However, little empirical research examines how users form mental models of robots, how they collaborate with them, and what factors contribute to the success or failure of human-robot collaboration. A two-year observational study of a collaborative human-robot system suggests that the factors disrupting the creation of common ground for interactive communication change at different levels of robot autonomy. Our observations of users collaborating with the remote robot showed differences in how the users reached common ground with the robot in terms of an accurate, shared understanding of the robot's context, planning, and actions - a process called grounding. We focus on how the types and levels of robot autonomy affect grounding. We also examine the challenges a highly autonomous system presents to people's ability to maintain a shared mental model of the robot  相似文献   
68.
The professional and economic challenges to psychologists posed by organized medicine have been stymied in the past by the Federal Trade Commission and by strict enforcement of the antitrust laws. Now that professionals' competition and consumer choice are being supported in the courts, the American Medical Association (AMA) is redoubling its efforts to retain a monopolistic hold on health care, hospital practice, and health insurance throughout the nation. Organized psychology, with the help of other professions and the Congress, has barely held the line against politically and economically stronger forces. The Association for the Advancement of Psychology and the American Psychological Association actively opposed the AMA's proposed legislation in 1981 and 1982 that would have allowed the AMA to circumvent valid law. The medical profession has actively worked to control all health care and deny psychologists hospital staff privileges, preventing group practice between physicians and psychologists, denying them health insurance reimbursement, and restricting psychological services to physician supervision. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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