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991.
This article traces the definition of the public interest from the Navy Department through the FRC, to the FCC, with regard to the right mixture of competition and monopoly in international radiotelegraphy and identifies foreign policy as an important policy area where regulatory autonomy is enhanced. Policymakers defined the public interest independently of industry pressure because of internal divisions in the industry and, more importantly, because the strategic and international dimensions of the policy area brought the Navy Department into the regulatory mix and prompted the Commission to adopt a realist, rather than a liberal, framework.  相似文献   
992.
In a previous paper (Hartley and Holt, 1971) the development of a three‐minute reasoning test was described, and its validity and reliability assessed. In this paper three experiments are reported which look in greater detail at these aspects of the test in different situations. The results of the experiments indicated that the test was less valid and was less reliable than was originally anticipated.  相似文献   
993.
994.
The graduate departments of adult education at 88 universities in the United States were surveyed for information pertinent to their programs in and about aging. Results show that 55% of the departments offer no courses dealing exclusively with education and aging. Only one department offers a program concentration per se in educational gerontology. Those adult education academic programs that have a seeming interest in education and aging typically offer only an isolated course or two. Much needs to be done if adult education programs are to begin preparing people to meet the learning needs of older adults.  相似文献   
995.
Goal-based scenarios (GBSs) have become a mainstay of Andersen Consulting’s 900 million dollar efforts to train its employees. Utilizing a theoretical framework based upon social constructivist theory, we create classroom learning environments that use theatrical elements to simulate real-world client engagements. The suspension of disbelief, however, is one factor that can be detrimental to human learning in immersive simulations. This paper describes one of our school designs, constructs a theoretical framework to support our approach, examines some of the factors associated with the suspension of disbelief, and makes recommendations for enhancing the authenticity of goal-based scenarios.  相似文献   
996.
This research investigates the inherent dilemma evident in attempts to promote decentralization initiatives in urban public schools. Detroit provides a natural experiment in decentralized education reform given both the collaborative and the competitive reform efforts that were advanced between 1988 and 1994. A collaborative partnership, the Detroit Compact, was created, and schools of empowerment and choice were partially implemented, conceptually designed to enlarge the community role in the operation of the schools. Results indicate that efforts at promoting decentralization, over time may produce counterpressures to recentralize decision making.  相似文献   
997.
998.
Two experiments used eye tracking to investigate a novel cueing approach for directing learner attention to low salience, high relevance aspects of a complex animation. In the first experiment, comprehension of a piano mechanism animation containing spreading-colour cues was compared with comprehension obtained with arrow cues or no cues. Eye tracking data revealed differences in learner attention patterns between the different experimental conditions. The second experiment used eye tracking with synchronized and non-synchronized cues to investigate the role of dynamic direction of attention in cueing effectiveness. Results of Experiment 1 showed that spreading-colour cues resulted in better targeting of attention to thematically relevant aspects and in higher comprehension scores than arrow cues or no cues. For Experiment 2, superior comprehension after the synchronized version together with eye tracking data indicated that cue effectiveness depended on attention direction being spatially and temporally coordinated with onsets of animation events having high thematic relevance to the learning task. The findings suggest the importance of perceptual cues and bottom-up processing.  相似文献   
999.
1000.
In this paper it is argued that virtual processes are dispensable fictions. The argument proceeds by a comparison with the phenomenon of quantum tunnelling. Building on an analysis of Lévy-Leblond and Balibar, it is argued that, although the phenomenon known as quantum tunnelling certainly occurs and is at the basis of many paradigmatic quantum effects, the implied conceptualization of it as a free particle burrowing through a potential barrier is flawed. An alpha particle, for example, does not exist as a free particle inside a uranium nucleus and then ??burrow through?? the massive potential barrier of the repulsive Coulomb potential: rather, it can be interpreted as existing in a bound state which gives it a corresponding (absolutely tiny, but) finite probability of appearing on the other side of the barrier. If the part of the state function representing the transmission through the barrier is conceived as representing a particle trajectory, the particle will have imaginary momentum and negative kinetic energy. A similar analysis then applies to virtual processes. For example, if (as in Hawking??s conception of black hole radiation) one imagines a pair of particles created at the Schwarzschild radius, one of which drops into the black hole, at its creation that particle will have imaginary momentum and negative kinetic energy; so will the pion that is imagined as mediating the nuclear exchange force on the standard model. In each case, it is argued, the phenomenon can be understood in terms of a finite probability of transmission predicted by quantum theory, without appealing to particle trajectories. The idea that a particle ??penetrates?? a barrier that it does not have the energy to surmount, or that a pair of particles is ??virtually?? produced one on either side of the Schwarzschild radius, in defiance of energy conservation, should be discarded as unphysical.  相似文献   
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