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971.
N. García-Chan L.J. Alvarez-Vázquez A. Martínez M.E. Vázquez-Méndez 《Journal of The Franklin Institute》2014
Within the framework of numerical modelling and multi-objective control of partial differential equations, in this work we deal with the problem of determining the optimal location of a new industrial plant. We take into account both economic and ecological objectives, and we look not only for the optimal location of the plant but also for the optimal management of its emissions rate. In order to do this, we introduce a mathematical model (a system of nonlinear parabolic partial differential equations) for the numerical simulation of air pollution. Based on this model, we formulate the problem in the field of multi-objective optimal control from a cooperative viewpoint, recalling the standard concept of Pareto-optimal solution, and pointing out the usefulness of Pareto-optimal frontier in the decision making process. Finally, a numerical algorithm – based on a characteristics/Galerkin discretization of the adjoint model – is proposed, and some numerical results for a hypothetical situation in the region of Galicia (NW Spain) are presented. 相似文献
972.
973.
Néstor Herran 《Science & Education》2012,21(3):335-353
This paper provides a first approach to the history of Ibérica, one of the most important popular science magazines published in Spain before the Civil War. Founded in 1914 by members of the Society of Jesus based at the Ebro Observatory, Ibérica reached a weekly circulation of about 10,000 in the mid 1920s, and was instrumental in extending science education in Jesuit education facilities and in developing a “reactionary modernist” culture that embraced Catholicism and modernisation. By focusing on its coverage of radioactivity and the radium industry, the article aims to examine the magazine’s popularising style and ideology, and to determine its role in the debates regarding the cultural value of science in the first decades of twentieth century Spain. 相似文献
974.
975.
S N Postlethwait 《American annals of the deaf》1966,111(5):657-660
976.
977.
978.
Developing an audiovisual notebook as a self‐learning tool in histology: Perceptions of teachers and students 下载免费PDF全文
Antonio Campos‐Sánchez Juan‐Antonio López‐Núñez Giuseppe Scionti Ingrid Garzón Miguel González‐Andrades Miguel Alaminos Tomás Sola 《Anatomical sciences education》2014,7(3):209-218
Videos can be used as didactic tools for self‐learning under several circumstances, including those cases in which students are responsible for the development of this resource as an audiovisual notebook. We compared students' and teachers' perceptions regarding the main features that an audiovisual notebook should include. Four questionnaires with items about information, images, text and music, and filmmaking were used to investigate students' (n = 115) and teachers' perceptions (n = 28) regarding the development of a video focused on a histological technique. The results show that both students and teachers significantly prioritize informative components, images and filmmaking more than text and music. The scores were significantly higher for teachers than for students for all four components analyzed. The highest scores were given to items related to practical and medically oriented elements, and the lowest values were given to theoretical and complementary elements. For most items, there were no differences between genders. A strong positive correlation was found between the scores given to each item by teachers and students. These results show that both students' and teachers' perceptions tend to coincide for most items, and suggest that audiovisual notebooks developed by students would emphasize the same items as those perceived by teachers to be the most relevant. Further, these findings suggest that the use of video as an audiovisual learning notebook would not only preserve the curricular objectives but would also offer the advantages of self‐learning processes. Anat Sci Educ 7: 209–218. © 2013 American Association of Anatomists. 相似文献
979.
Christopher N. Candlin 《Cultura y Educación》2013,25(7-8):33-53
Se exponen en este artículo los principios que deben regir la programación de tareas en la enseñanza de lenguas extranjeras y se ofrecen vías para su implementación. 相似文献
980.
Jan N. Hughes 《Psychology in the schools》1986,23(1):59-63
The majority of unserved and underserved handicapped children live in rural America (Sher, 1978). One obstacle to serving these children is a lack of qualified staff (Helge, 1981). The turnover rates for rural and urban school psychologists in Virginia were determined for the years 1977–78 through 1979–80: the rate for rurai school psychologists is four times the rate for urban school psychologists (p<.001). Rural school psychologists who terminated employment and rural school psychologists who remained were surveyed on selected background variables in 1981. School psychologists who remained were much more likely than those who left to have been raised in a nonurban community. Implications for training programs are discussed. 相似文献