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231.
Although the principle of holography was conceived as long ago as 1947, interest was limited until the advent of the laser in 1960 made possible the off-axis holography widely used today. Since then holography has found many applications and become so well known outside the laboratory as to be a recognized art form. Within the last few years considerable progress has also been made in acoustic holography. 相似文献
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Measuring innovative performance: is there an advantage in using multiple indicators? 总被引:10,自引:0,他引:10
The innovative performance of companies has been studied quite extensively and for a long period of time. However, the results of many studies have not yet led to a generally accepted indicator of innovative performance or a common set of indicators. So far the variety in terms of constructs, measurements, samples, industries and countries has been substantial. This paper studies the innovative performance of a large international sample of nearly 1200 companies in four high-tech industries, using a variety of indicators. These indicators range from R&D inputs, patent counts and patent citations to new product announcements. The study establishes that a composite construct based on these four indicators clearly catches a latent variable ‘innovative performance’. However, our findings also suggest that the statistical overlap between these indicators is that strong that future research might also consider using any of these indicators to measure the innovative performance of companies in high-tech industries. 相似文献
234.
Ji Shen Patrick C. Gibbons John F. Wiegers Ann P. McMahon 《Journal of Science Teacher Education》2007,18(3):431-459
We present a practical way of adapting and using four research-based assessments for different purposes in an electricity
and magnetism course for K-8 science teachers. The course is designed to accomplish conceptual change toward accepted scientific
conceptions as well as introducing teachers to materials and activities appropriate for their classrooms. Our data support
that using the research-based tests to identify alternative conceptions and discuss test results with teachers is a promising
way to use the knowledge of alternative conceptions in professional development. We also identify some mismatches between
the research of conceptual change and its use in programs of professional development.
相似文献
Ji ShenEmail: |
235.
Berent GP Kelly RR Aldersley S Schmitz KL Khalsa BK Panara J Keenan S 《Journal of deaf studies and deaf education》2007,12(1):8-24
Focus-on-form English teaching methods are designed to facilitate second-language learners' noticing of target language input, where "noticing" is an acquisitional prerequisite for the comprehension, processing, and eventual integration of new grammatical knowledge. While primarily designed for teaching hearing second-language learners, many focus-on-form methods lend themselves to visual presentation. This article reports the results of classroom research on the visually based implementation of focus-on-form methods with deaf college students learning English. Two of 3 groups of deaf students received focus-on-form instruction during a 10-week remedial grammar course; a third control group received grammatical instruction that did not involve focus-on-form methods. The 2 experimental groups exhibited significantly greater improvement in English grammatical knowledge relative to the control group. These results validate the efficacy of visually based focus-on-form English instruction for deaf students of English and set the stage for the continual search for innovative and effective English teaching methodologies. 相似文献
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Kantorski Brinley Sanford-Dolly Camellia W. Commisso Danielle R. Pollock John A. 《Educational technology research and development : ETR & D》2019,67(3):711-731
Backward design is a well-established design strategy that has been used to produce educational curriculum for decades. While traditionally used to plan and create classroom-based curriculum, in this paper we explore the use of backward design as a design strategy for the development of an educational mobile application, BiblioTech? “CityHacks: In Search of Sleep.” We discuss the process from initial conception to launch and updates, as well as plans for future research.
相似文献