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71.
Michael Andrew Kovacs 《Journal of Earthquake Engineering》2019,23(5):750-770
Controlled rocking heavy timber walls are designed to rock on their foundations in response to earthquakes. For regions of moderate seismicity, it is proposed that this rocking behaviour can be adequately controlled using only post-tensioning, even with a large force-reduction factor and no supplemental energy dissipation. This article presents a force-based design procedure for controlled rocking cross-laminated timber walls without supplemental energy dissipation, including a method for estimating higher mode effects. Fragility analyses of three prototype walls demonstrate that the procedure can limit the probability of collapse to <10% during a maximum considered earthquake in a region of moderate seismicity. 相似文献
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Michael Pease Blanca Pérez-Lapeña Christopher Lant 《Journal of Geography in Higher Education》2019,43(1):40-55
This paper describes environmental systems games developed for energy and water resource use designed to be adaptable from high school to undergraduate use. Two of the games are computer simulations with adjustable levels of difficulty that can be done in a computer lab or as a homework assignment. The third is a peer-to-peer roleplayer game designed for an immersive in-class simulation. For the energy and the peer-to-peer water games, we describe (1) the overall strategy or story line adopted, (2) the manner in which the game is played by students in a classroom setting, (3) the use of scientific literature in conceptualizing and parameterizing the game, and (4) possible game extensions. Preliminary data from use at the undergraduate level shows that the games are very well-received by students and, consistent with other research on quasi-experimental simulations, likely enhance learning outcomes. 相似文献
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Is urbanization good for the environment? This paper establishes a simple core–periphery model with monocentric cities, which comprises key forces that shape the structure and interrelation of cities to study the impact of the urban evolution on the environment. We focus on global warming and the potential of unfettered market forces to economize on emissions. The model parameters are chosen to match the dichotomy between average “large” and “small” cities in the urban geography of the United States, and the sectoral greenhouse gas emissions recorded for the United States. Based on numerical analyzes we find that a forced switch to a system with equally sized cities reduces total emissions. Second, any city driver which pronounces the asymmetry between the core and the periphery drives up emissions in the total city system, too, and the endogenous adjustment of the urban system accounts for the bulk of the change in emissions. Third, none of the city drivers gives rise to an urban environmental Kuznets curve according to our numerical simulations. Finally, the welfare‐maximizing allocation tends to involve dispersion of cities and the more so the higher is the marginal damage from pollution. 相似文献
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Eric Plutzer Michael B. Berkman James Honaker Christopher Ojeda Anne Whitesell 《政策研究杂志》2019,47(3):712-734
Welfare policy is multidimensional because of the political compromises, competing goals, and federalist structure underpinning it. This complexity has hindered measurement and, therefore, the comparability of research on race and welfare policy. This paper describes a measurement strategy that is transparent, replicable, and attuned to matching the assumptions of statistical models to the policy process. We demonstrate that this strategy leads to more nuanced conclusions regarding the relationship between minority caseloads and the flexibility of state welfare policies. The strategy and recommendations are adaptable to research agendas that scholars bring to the comparative study of welfare in the U.S. states, countries, or other units—and to other complex policies enacted in federal systems. 相似文献
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