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71.
72.
F B Rogers 《Bulletin of the Medical Library Association》1983,71(2):245-248
73.
The study examines selected roles of the information sector in the national economy. Among the findings are the following: (1) the information sector conducts relatively little international trade, in comparison to its domestic activity. Roughly 12% of U.S. exports are attributable to the information sector; over 97% of the sector's output is sold within the U.S.; and the sector's exports account for only a small fraction of 1% of GNP. (2) The historical pattern of employment shows that the portion of information workers has risen from 8% of the U.S. work force in 1870 to 41% in 1970. Relatively little of this growth is the result of new technological innovations such as telephones, radio, television and, more recently, computers. Rather, the growth of public and private bureaucracies, which now total 26% of our total work force, largely explains the growth of the sector. (3) Unemployment within the information sector has consistently been lower than in either the manufacturing or agricultural sectors of the national economy. (4) Since 1967, the high technology elements of the information sector, such as electronic components, computers and telecommunications equipment have experienced appreciably less price rise than has the economy as a whole. However, over the same time period, the service elements of the sector, including finance and insurance, education and medical care, have experienced greater rates of inflation than has the economy as a whole. 相似文献
74.
75.
Zheng-Guang Wu Ju H. Park Hongye Su Jian Chu 《Journal of The Franklin Institute》2012,349(6):2136-2150
In this paper, the problem of stochastic stability analysis is considered for piecewise homogeneous Markovian jump neural networks with both discrete and distributed delays by use of linear matrix inequality (LMI) method. Based on a Lyapunov functional that accounts for the mixed time-delays, a delay-dependent stability condition is given, which is formulated by LMIs and thus can be easily checked. Some special cases are also investigated. Finally, a numerical example is given to show the validness of the proposed result. 相似文献
76.
Increasingly, firms recognize the strategic implications of front-end product design for improving total cost effectiveness. Computer-aided design (CAD) is becoming firms’ competitive weapon beyond its traditional function as a product design tool. Yet, it is unclear how the full potential of IT system, particularly the usage patterns of 3D CAD system, may be realized through organizational capabilities. This paper presents a model of IT system configurations and CAD usage patterns. Next, a typology of IT system configurations is presented based on (1) the degree of CAD integration between assembly makers and suppliers and (2) the structure of product design information (i.e., product architecture). The product architecture of four electronic firms illustrates that information integration through organizational capabilities is more important than IT investment itself. The findings suggest that a Korean firm accomplishes a greater level of IT integration compared to the other two Japanese firms and thus attain better market performance. This study offers valuable insight on effective IT integration strategy for competitive advantage in the global market. 相似文献
77.
Appropriate intellectual property protection and economic growth in countries at different levels of development 总被引:1,自引:0,他引:1
This paper examines how the role of patents and utility models in innovation and economic growth varies by level of economic development. Using a panel dataset of over 70 countries, we find that patent protection is an important determinant of innovation and that patentable innovations contribute to economic growth in developed countries, but not in developing. Instead, in developing economies, a minor form of intellectual property rights (IPRs) - namely utility models - is conducive to innovation and growth, controlling for other factors. Using Korean firm level data as a case study, we find that utility model innovations contribute to firm performance when firms are technologically lagging and that those minor innovations can be a learning device and thus a stepping stone for developing more patentable inventions later on. Upon reaching higher levels of technological capabilities, firms become more reliant upon patents and less on utility models. Thus the lesson here is that patent protection enhances innovation and economic growth in countries where the capacity to conduct innovative research exists. Where this capacity is weaker, a system that provides incentives to conduct minor, incremental inventions is more conducive to growth. The significance of this paper is to emphasize the importance not just of the strength of IPRs but of the appropriate type of IPRs for economic development. 相似文献
78.
The purpose of this case study, informed by a Lakatosian perspective, is to identify how an alternative conception that originates in present learning but is related directly to subsequent learning contexts can be constructed. Before the study, one of the authors found by accident that a student who had learned about Avogadro's principle and chemical reaction in South Korea constructed an alternative conception related to the volume of gas. Later, we identified seven Korean high school students with the alternative conception through a test and analyzed their underlying understandings qualitatively through interviews. The results show that they had a scientific conception—core conception—and intuitive assumptions about implicit information of external representations—implicit assumptions—in common. The students' implicit assumptions could be divided into three types again: core assumption, auxiliary assumption, and context-inducing assumption. The core assumption, like the core conception, played a significant role in constructing the alternative conception (hard core), while the auxiliary assumptions were incomplete implicit assumptions to protect the alternative conception (protective belt). The context-inducing assumption was an implicit assumption bringing the context of the subsequent curriculum, and the core conception and the core assumption could be interpreted in this induced context. At the end of the study, the implications related to learning progressions were discussed. 相似文献
79.
Insim Park 《Educational Research and Evaluation》2013,19(5):461-485
This study explored the effects of teacher commitment on student achievement. Three teacher commitment dimensions of organizational, professional, and student commitment were derived. The three-dimensional teacher commitment measurement model was tested by a confirmatory factor analysis. Then, the relationships among individual and organizational variables, teacher commitment, and student achievement were analyzed by a 2-level hierarchical linear modeling method. As the results, the greater portions of teacher commitment and student achievement variances were within schools. The individual and organizational variables had differential impacts on each teacher commitment dimension. Finally, while teacher commitment effects on student achievement were differentially found depending on teacher commitment dimensions at the individual level, there was no evidence to support significant impacts of teacher commitment on student achievement at the organizational level. 相似文献
80.
The present study seeks to identify factors among university students that may be associated with homophobic attitudes and whether homophobia may be reduced by educational interventions, such as knowledge-based curricula found in college sexuality courses. Participants were 128 undergraduate students attending a small, private university in the northwestern region of the United States. At the beginning and end of the fall semester 2004, survey packets consisting of a demographic questionnaire, the Sexual Opinion Survey, the Homophobia Scale, a sexual knowledge survey, and the Bem Sex Role Inventory were administered to students attending a human sexuality class and a comparison group of students enrolled in professional and social science introductory courses. Relative to the comparison group, homophobia levels significantly decreased over the course of the semester among students attending the sexuality class. The effect of attending the class on reducing homophobia was partially mediated by an increase in self-reported knowledge about sexual matters. Taken together, these results suggest that the knowledge-based curriculum of sexuality courses may play an important role in affecting broader attitudes about sexuality among college students, including attitudes about homosexuality. 相似文献