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991.
ABSTRACT: The assessment of learning gains of students in science and other disciplines is becoming a reality following the gradual shift from the traditional style of teaching to a curriculum-based assessment of learning outcomes. The degree to which students perceive to have obtained the outcomes of a course can be measured through an assessment of students' learning gains. This study evaluated the perceived learning gains of freshmen students in an introductory class FSC 110-Introduction to Human Nutrition and Food Science (FSC 110)-over a 4-semester period. Students used the Assessment of Learning Gains Survey Instrument, developed by the Wisconsin Center for Education Research, to assess the level of their perceived learning gains. The data collected indicated that, overall, students favorably perceived their learning gains in the course. Through the instrument, students identified areas of the course that they perceived to have contributed positively to their learning experiences and those they perceived to have not contributed in any meaningful way to their learning experiences. The students' perception of their learning gains could be useful to the instructor because it offers opportunities to revise the course with respect to delivery method, assessment methods and tools, and course resources, and to improve individual support given to students to enhance their learning experience. Such alterations in pedagogy could lead to significant improvements in course quality, which could be archived and transferred to subsequent classes.  相似文献   
992.
In Part 1 of this article, we had introduced the reader to some basic concepts of fractals and some operational algorithms to characterize them. We had also pointed out and clarified some common misconceptions about fractals. In this part we apply the fractal concepts to large-scale structures in the Universe. In particular we discuss the claim by some investigators that the distribution of galaxies in the Universe is a fractal. This is contrary to the standard view that the Universe is homogeneous and isotropic on large scales. Also discussed is the controversy as to whether the matter distribution in the Universe is a fractal on large-scales.  相似文献   
993.
The paper opens with a brief statement of the two conceptual frameworks on which the analysis is based. The author then takes up in turn the five classical methods of shaping students' learning: didactic instruction in the form of lectures; discussion methods; practical work in laboratories, studios etc; provision for the students' private study, including individualized learning techniques and computer‐based methods; and the assessment of students' progress. He outlines the main departures from customary practice in each area, with special attention to small‐group techniques. Finally, since a critical aspect of development is the dissemination of fresh techniques, there is a section on development strategy.  相似文献   
994.
Three experiments, using rats, demonstrated the encoding of a food unconditioned stimulus (US) in a simple Pavlovian conditioning paradigm. In all three studies, one stimulus was used to signal the delivery of pellets and a different stimulus was used to signal the delivery of sucrose. In Experiment 1, postconditioning devaluation of one of the food USs selectively reduced the frequency of conditioned magazine-directed behavior during the stimulus trained with that US. In Experiment 2, transfer of the stimuli to instrumental responses resulted in selective depression of the response trained with a different outcome. In Experiment 3, acquisition of stimulus-outcome learning was impaired by unsignaled intertrial presentations of the same outcome but not of a different outcome. These results indicate that a detailed representation of the outcome is encoded in the normal course of Pavlovian conditioning.  相似文献   
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During the last decade it has been argued by some investigators that the distribution of galaxies in the Universe is a fractal. This is contrary to the standard view that the Universe is homogeneous and isotropic on large scales. In this article, the basic concepts of fractals and their characterization are introduced with the help of simple examples. The applications of these concepts in the context of cosmology will be discussed in the second part. A K Mittal is currently a visiting scientist at Harish-Chandra Research Institute, Allahabad, on leave from the University of Allahabad. His research interests include chaos, fractals and their applications, partleularly in cosmology and in weather prodiction. T H Seshadri is at the Department of Physics and Astrophysics, University of Delhi. He is presently on lien from Harish-Chandra Research Institute, Allahabad. Areas of his interest include cosmic microwave background radiation, large scale structures in the Universe and application of fractals in these.  相似文献   
1000.
This article gives the principle of hydrodynamic lubrication and also presents the new phenomenon of levitating drops over liquid film flow, which is explained using hydrodynamic lubrication theory.  相似文献   
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