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981.
This paper is devoted to the identification of analytic signals and to find a solution to the following problem. Given a realization of an analytic signal, it is necessary to find the analytic function by which the signal is described. The proposed approach to this problem is based on relatively simple relationships existing between many analytic signals and their respective derivatives. These relationships are closely related to the properties of the dynamic systems which generate the signals under investigation. Simple identification procedures are described and tested by means of computer simulation. 相似文献
982.
Environment and Policy Factors Shaping Global E-Commerce Diffusion: A Cross-Country Comparison 总被引:1,自引:0,他引:1
This article examines the key global, environmental and policy factors that act as determinants of e-commerce diffusion. It is based on systematic comparison of case studies from 10 countries--Brazil, China, Denmark, France, Germany, Mexico, Japan, Singapore, Taiwan, and the United States. It finds that B2B e-commerce seems to be driven by global forces, whereas B2C seems to be more of a local phenomenon. A preliminary explanation for this difference is that B2B is driven by global competition and MNCs that "push" e-commerce to their global suppliers, customers, and subsidiaries. This in turn creates pressures on local companies to adopt e-commerce to stay competitive. In contrast, B2C is "pulled" by consumer markets, which are mainly local and therefore divergent. While all consumers desire convenience and low prices, consumer preferences and values, national culture, and distribution systems differ markedly across countries and define differences in local consumer markets. These findings support the transformation perspective about globalization and its impacts. In terms of policy, the case studies suggest that enabling policies such as trade and telecommunications liberalization are likely to have the biggest impact on e-commerce, by making ICT and Internet access more affordable to firms and consumers, and increasing pressure on firms to adopt e-commerce to compete. Specific e-commerce legislation appears not to have as big an impact, although inadequate protection for both buyers and sellers in some countries suggests that mechanisms need to be developed to ensure greater confidence in doing business online. 相似文献
983.
984.
985.
Praveen Sharma P. K. Sharma D.Sc. J. Pramod L. K. Kothari Rashmi Ranka Sushma Sharma 《Indian journal of clinical biochemistry : IJCB》1989,4(1):62-64
Sixteen weeks of chronic vitamin C deficiency, induced in guinea pigs by restricted vitamin C intake, resulted in a marked
increase in the serum total LDL- and VLDL- cholesterol, triglycerides and total lipids. HDL-cholesterol decreased resulting
in a highly significant increase in LDL/HDL ratio. The results reconfirm that vitamin C deficiency causes changes in blood
lipid profile which could promote atherogenesis. 相似文献
986.
Paul L. Hill Rose A. Shaw Jan R. Taylor Brittan L. Hallar 《Innovative Higher Education》2011,36(1):19-27
Although progress has been made, greater efforts are needed to promote faculty diversity at the college and university levels,
especially in STEM fields. Thus, it is important to elucidate best practices both for increasing awareness of diversity issues
pertaining to higher education and for implementing change. This article focuses on the outcomes of a diversity workshop for
college and university faculty hosted by the West Virginia Higher Education Policy Commission, Division of Science and Research.
More specifically, it elucidates how participation in the workshop translated into practice at the faculty participants’ home
institutions. 相似文献
987.
This study examines whether levels of father engagement (e.g., verbal stimulation, caregiving, and physical play) vary by race/ethnicity using a model that controls for fathers' human capital, mental health, and family relationships. It also tests whether the models work similarly across race/ethnic groups. Its sample of N=5,089 infants and their families is drawn from the Early Childhood Longitudinal Study - Birth Cohort (ECLS-B). We found that, after including controls, African American and Latino fathers had higher levels of engagement in caregiving and physical play activities than White fathers. There were no differences in verbal stimulation activities across race/ethnicity. Fathers' education (college level) predicted more verbally stimulating activities whereas fathers' report of couple conflict predicted less caregiving and physical play. Although levels of engagement differed across the groups, the overall models did not differ by race/ethnicity, except for physical play. African American mothers who reported high levels of depressive symptoms had partners who engaged in more physical play than White mothers with high levels of depressive symptoms. 相似文献
988.
Susan L. O'Rourke Marie Martin 《British journal of educational technology : journal of the Council for Educational Technology》2011,42(5):875-882
This paper describes the development of a virtual learning environment using a blend of collaborative technologies and human resources to provide US preservice teachers with an authentic experience of another culture. A core design component is the use of ‘embedded instructors’ who are natives of and living in the target country (N. Ireland) while delivering the course in the USA. The wider issue of the potential depersonalisation of online learning is also addressed, and effective strategies for promoting the human dimension and sustaining learner engagement are described. In the context of globalisation, as well as of the constantly increasing provision of online courses, the course model could be of interest to both the academic and the corporate world. 相似文献
989.
990.
This study examined parent-child emotion discourse, children's independent social information processing, and social skills outcomes in 146 families of 8-year-olds with and without developmental delays. Children's emergent social-cognitive understanding (internal state understanding, perspective taking, and causal reasoning and problem solving) was coded in the context of parent-child conversations about emotion, and children were interviewed separately to assess social problem solving. Mothers, fathers, and teachers reported on children's social skills. The proposed strengths-based model partially accounted for social skills differences between typically developing children and children with delays. A multigroup analysis of the model linking emotion discourse to social skills through children's prosocial problem solving suggested that processes operated similarly for the two groups. Implications for ecologically focused prevention and intervention are discussed. 相似文献