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131.
132.
《Communications in Nonlinear Science & Numerical Simulation》2014,19(3):570-577
Assume that the households of a country are socially classified according to the monthly total income, and that they can be part of a lower, a middle or an upper class. By using multi-agent systems, here we model and simulate the economic evolution of households which earn a wage, pay taxes and invest in education. The return of the education investment is monthly added to the salary of the family, and it is function of the corresponding grand total put in education along the time. When a family is unemployed, we consider that it receives cash due to a social program made by the government. The time evolution of the percentages of households belonging to each class is investigated by varying the government investment in such a program of cash transfer and the proportion of employed households in the population. We show that the government should invest in the unemployed lower class if it intends a growth of the middle class. We also propose and analyze a mean-field approximation written in terms of ordinary differential equations. In addition, we verify that our model fits real data from Brazil, in the period between 2003 (when the cash transfer program Bolsa Família was launched) and 2011. 相似文献
133.
Possibilities for global governance of converging technologies 总被引:2,自引:2,他引:0
Mihail C. Roco 《Journal of nanoparticle research》2008,10(1):11-29
The convergence of nanotechnology, modern biology, the digital revolution and cognitive sciences will bring about tremendous
improvements in transformative tools, generate new products and services, enable opportunities to meet and enhance human potential
and social achievements, and in time reshape societal relationships. This paper focuses on the progress made in governance
of such converging, emerging technologies and suggests possibilities for a global approach. Specifically, this paper suggests
creating a multidisciplinary forum or a consultative coordinating group with members from various countries to address globally
governance of converging, emerging technologies. The proposed framework for governance of converging technologies calls for
four key functions: supporting the transformative impact of the new technologies; advancing responsible development that includes
health, safety and ethical concerns; encouraging national and global partnerships; and establishing commitments to long-term
planning and investments centered on human development. Principles of good governance guiding these functions include participation
of all those who are forging or affected by the new technologies, transparency of governance strategies, responsibility of
each participating stakeholder, and effective strategic planning. Introduction and management of converging technologies must
be done with respect for immediate concerns, such as privacy, access to medical advancements, and potential human health effects.
At the same time, introduction and management should also be done with respect for longer-term concerns, such as preserving
human integrity, dignity and welfare. The suggested governance functions apply to four levels of governance: (a) adapting
existing regulations and organizations; (b) establishing new programs, regulations and organizations specifically to handle
converging technologies; (c) building capacity for addressing these issues into national policies and institutions; and (d)
making international agreements and partnerships. Several possibilities for improving the governance of converging technologies
in the global self-regulating ecosystem are recommended: using open-source and incentive-based models, establishing corresponding
science and engineering platforms, empowering the stakeholders and promoting partnerships among them, implementing long-term
planning that includes international perspectives, and institute voluntary and science-based measures for risk management.
相似文献
Mihail C. RocoEmail: |
134.
One promising approach for connecting undergraduate content coursework to secondary teaching is using teacher-created representations of practice. Using these representations effectively requires seeing teachers' use of mathematical knowledge in the work of teaching. We argue that the dimensions of Rowland's (2013) Knowledge Quartet, especially Foundation and Contingency, form a fruitful framework for this purpose. We contribute an analytic framework to characterize the quality of mathematical knowledge observed in the Foundation and Contingency dimensions, developed using a purposive sampling from over 300 representations. These representations all featured geometry teaching. We showcase the framework with examples of "high" and "developing" Foundation and Contingency.Then, we compare our coding along these dimensions with performance on a measure of mathematical knowledge for teaching geometry. Finally, we describe the potential for generalizing this framework to other domains, such as algebra and mathematical modeling. 相似文献