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Emergence of new industries from evolving technologies is critical to the global economy, yet has been relatively understudied due to the paucity of available data. This study draws lessons on industry emergence, by analyzing how a solid-state lighting (SSL) industry grew out of light emitting diode (LED) technologies that evolved for half a century, with participation by tens of thousands of researchers in universities, national laboratories, and firms. Using data on publications, patents, and firms combined with business history we trace the evolution of SSL through a succession of market niches. At times a few researchers with unorthodox research approaches made breakthroughs that greatly advanced particular technology trajectories and pushed LED research in unexpected directions. A succession of LED market niches advanced the technology and provided profits to incentivize continuing research while reducing cost and improving efficacy of LEDs. Innovating firms developed a thicket of patents and captured substantial profit, but were embroiled in extensive litigation that was ultimately resolved through cross-licensing. A major new generation of lighting products is now disrupting the traditional lighting industry. Although the leading incumbent lighting firms all invested early and heavily in SSL, the industry's future leadership is uncertain. 相似文献
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Kenneth O. Gangel 《Religious education (Chicago, Ill.)》2013,108(4):518-525
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Abstract A study was made of the relationship of physique and developmental level, determined by use of the Wetzel Grid, to performance of junior high boys on four fitness tests: pull-ups, 50-yd. dash, standing broad jump, and softball throw. Subjects of different physique groups (heavy, medium, and thin) who were alike developmentally (accelerated, normal, and retarded) differed more markedly in performance than did subjects of different developmental levels who were alike with regard to physique. Subjects who were medium in physique and normal in development were the best performers. Subjects of heavy physique (many overweight) were the poorest performers. This would seem to indicate the need for a restudy of classification methods, particularly when norms are to be used for evaluating performance. 相似文献
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An earlier version of this paper was presented to the AEJ convention at Boulder, Colorado in 1973 by Dr. Milan Meeske for the authors. Dr. O'Keefe is an associate professor of communication at Florida Technological University where Mr. Sheinkopf is a student. 相似文献
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