This paper examines research on the diffusion of innovation, the final stage in the process of technological change. The focus rests primarily on two traditions in diffusion research: that of economists and that of sociologists. Diffusion researchers in these and related disciplines have made significant contributions to the understanding of the dynamics of processes of change; yet the state of the art in diffusion research is not equal to the sum of its parts. This is due in large measure to disciplinary parochialism: scholars have concentrated on those innovations, diffusion environments, explanatory variables, and analytical methodologies which are most compatible with their particular disciplines, despite the fact that diffusion is not a discipline-specific phenomenon. Deficiencies in current understanding of diffusion are examined in the context of this and other significant problems. The paper concludes by considering the policy relevance of diffusion research and suggesting issues with which future research might productively be concerned.The following individuals have been most helpful in stimulating and directing my interest in this subject and in criticizing this paper: Richard R. Nelson of Yale University and the following members of the Faculty Seminar on Innovation and Social Change, Institute of Public Policy Studies, University of Michigan: Michael Moch, Lawrence Mohr, Everett Rogers, Herbert Schuette, Jack Walker, and Sidney Winter. 相似文献
"We are therefore giving priority to setting up economic planning machinery with industry and employee co-operation to restore strong but balanced economic growth."—E. G. Whitlam, The Australian , 14th May, 1973. 相似文献
The complex nature of medieval Arabic compilations, with their evidence of manifold pieces and layers of diverse (older) text material, has been puzzling to many scholars of Islam. It has even caused some researchers to question the authenticity and credibility of information contained in these texts—and their value as historical sources—altogether.
An inquiry into the theoretical controversies at issue here constitutes the starting point of this article. Additionally, we will look at the categories and terms more frequently used in Western studies of the sources of Arabic compilations from about the eighth to the eleventh century Common Era (CE). The second part of the article offers an extensively annotated catalogue of categories and terms. This terminology, it is hoped, will help advance the assessment of classical Arabic compilations, for it takes the actual circumstances of the transmission of knowledge and the working techniques of compilers in medieval Islam into proper consideration. In conclusion, the paper illustrates how the proposed categories and terms are to be applied. It will become clear that the application of this kind of refined source-critical examination of individual classical Arabic texts is instrumental to a better understanding of medieval Muslim scholarship in general. 相似文献
In a second test of an arthropod saturation hypothesis, we analyzed if the on-campus Anthropology Research Facility (ARF) at the University of Tennessee, Knoxville, with its 20+ yr history of carcass enrichment, is comparable to non-enriched sites in community structure of predatory and parasitic arthropods that prey upon the sarcosaprophagous fauna. Over a 12-day period in June 1998, using pitfall traps and sweep nets, 10,065 predaceous, parasitic, and hematophagous (blood-feeding) arthropods were collected from freshly euthanized pigs (Sus scrofa L.) placed at ARF and at three surrounding sites various distances away (S2-S4). The community structure of these organisms was comparable in most paired-site tests with respect to species composition, colonization rates, and evenness of pitfall-trap abundances on a per carcass basis. Site differences were found in rarefaction tests of both sweep-net and pitfall-trap taxa and in tests of taxonomic evenness and ranked abundances of sweep-net samples. Despite these differences, no evidence was found that the predatory/parasitic fauna at ARF was impoverished with fewer but larger populations as a result of carcass enrichment. Comparison of the sarcosaprophagous and predatory/parasitic faunas revealed a tighter (and more predictable) linkage between carrion feeders (sarcosaprovores) and their carrion than between carrion feeders and their natural enemies (predators and parasitoids), leading us to conclude that ARF is more representative of surrounding sites with respect to the sarcosaprovore component than to the predatory/parasitic component within the larger carrion-arthropod community. 相似文献
Suffocation by inhaled gases has been reported involving a variety of gases. We report a case of suicidal asphyxiation by forced replacement of oxygen with helium by using a complex homemade mask. In this case, a young woman researched suicide on the Internet and found an advocated method of suicide using helium. To our knowledge, there is only 1 previously reported case of suicidal asphyxia by using helium. 相似文献