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91.
There are many barriers and challenges associated with climate change communication focused on promoting community-based action for sustainable futures. Of particular interest is the challenge to embed community perspectives in a communication process of climate change solutions. In this paper we argue that 3D interactive simulations using design inquiry as a development process, can be an effective way of communicating climate change solutions and multiple community responses. People are more likely to engage with the challenges associated with complexity of climate change at the local level when their perspectives are integrated into viable and multiple pathways for action. Future scenarios of change processes situated in local experiences in compelling and interactive ways can be disseminated holistically by making links between scientific, social, political, economic and cultural elements. Design inquiry, as a research approach, integrates contextual knowledge into communication processes to aid imagining, re-thinking and reembodying viable pathways that explore the kinds of futures we collectively envision. This paper examines the contributions that design inquiry makes to climate change communication using an interactive simulation environment for designing futures. We discuss these ideas using the example of the Future Delta project, a virtual 3D environment that enables the exploration and simulation of multiple community-based climate change solutions in the Corporation of Delta, British Columbia.  相似文献   
92.
煤矿综放面窄煤柱尺寸较小,并且受到采动影响,往往产生较大的变形和移动,其破坏规律异常复杂。以某矿13278工作面为例,应用三维有限差分计算软件FLAC3D分析运料巷围岩及煤柱在工作面倾向、走向方向的破坏特征,得出该工作面生产过程中需要加强支护,防止出现安全事故。  相似文献   
93.
El sistema chino de relaciones laborales consiste en un modelo de consulta colectiva dirigida por el Gobierno y un método de gestión por cuotas heredado de la economía planificada. Gobierno y sindicatos colaboran para lograr cuotas de cobertura, sobre todo a nivel empresarial. Aunque consiguen salvar las reticencias empresariales, la ausencia de verdadera negociación colectiva priva de sustancia los convenios firmados. A partir de entrevistas y de fuentes documentales, los autores concluyen que el Gobierno pretende institucionalizar un marco de relaciones laborales para contener el creciente descontento laboral pero posponiendo pragmáticamente la auténtica negociación colectiva en aras de la estabilidad y el crecimiento.  相似文献   
94.
The objective of this article is to study (understand and forecast) spot metal price levels and changes at monthly, quarterly, and annual frequencies. Data consists of metal-commodity prices at a monthly and quarterly frequencies from 1957 to 2012, extracted from the IFS, and annual data, provided from 1900 to 2010 by the U.S. Geological Survey (USGS). We also employ the (relatively large) list of co-variates used in Welch and Goyal (2008) and in Hong and Yogo (2009).We investigate short- and long-run comovement by applying the techniques and the tests proposed in the common-feature literature. One of the main contributions of this paper is to understand the short-run dynamics of metal prices. We show theoretically that there must be a positive correlation between metal-price variation and industrial-production variation if metal supply is held fixed in the short run when demand is optimally chosen taking into account optimal production for the industrial sector. This is simply a consequence of the derived-demand model for cost-minimizing firms. Our empirical evidence fully supports this theoretical result, with overwhelming evidence that cycles in metal prices are synchronized with those in industrial production. This evidence is stronger regarding the global economy but holds as well for the U.S. economy to a lesser degree.Regarding out-of-sample forecasts, our main contribution is to show the benefits of forecast-combination techniques, which outperform individual-model forecasts – including the random-walk model. We use a variety of models (linear and non-linear, single equation and multivariate) and a variety of co-variates and functional forms to forecast the returns and prices of metal commodities. Using a large number of models (N large) and a large number of time periods (T large), we apply the techniques put forth by the common-feature literature on forecast combinations. Empirically, we show that models incorporating (short-run) common-cycle restrictions perform better than unrestricted models, with an important role for industrial production as a predictor for metal-price variation.  相似文献   
95.
Using returns to scale as a conceptual foundation, we explore how R&D-related earnings performance and earnings variability depend upon firm size. We find that the positive association between the level of future earnings and R&D intensity increases with firm size, and that the positive association between the volatility of future earnings and R&D intensity decreases with firm size, consistent with R&D productivity increasing with scale. We also show that R&D scale is associated with lower market returns, consistent with the idea that R&D investment risk declines with scale.  相似文献   
96.
We study the propagation of global investment risk across markets through the granular view of institutional investors. Applying the conditional value-at-risk estimation to micro-level weekly observations of international mutual funds between 2003 and 2011, we find that idiosyncratic shocks to large institutional investors explain both aggregate market risk and cross-market risk interdependence. Conditional on the US capital markets being in financial distress, idiosyncratic shocks to the top 10% largest funds investing in the US explain about 40% of the risk fluctuations in other non-US markets. The findings are also economically and statistically significant for the top largest funds investing in non-US markets, with the effects becoming especially large during the global financial crisis of 2007–09. These results are robust after controlling for common risk factors and applying alternative measures of idiosyncratic shocks.  相似文献   
97.
This paper analyses the extent to which the level of bank competition influences monetary policy transmission. Using a large panel dataset of 978 banks from 55 countries, and employing the Lerner index model as a measure of market structure, our results show that an increase in banking sector competition weakens the effectiveness of monetary policy on bank lending. The findings are robust to a broad array of sensitivity checks including control of alternative measurements of the Lerner index, different samples and different methodological specifications. By extension, these results have important policy implications for regulators in assessing the effectiveness of monetary policy transmission mechanisms.  相似文献   
98.
任务型教学法在提高学生独立思考,应用语言表达自己思想和全面看问题方面的确有3P教学所不能及的效果。高职英语阅读教学更需要引入任务型范式来提高其英语应用能力。  相似文献   
99.
在对诠释3G以及掌上数字图书馆概念的基础上,分析了3G技术对掌上数字图书馆高校受众的影响,探讨了在3G技术支持下的高校掌上移动数字图书馆的发展前景及其服务方向与趋势。  相似文献   
100.
This paper examines the effect of unexpected exchange rate movements on U.S. shareholder wealth. Empirical results based on a sample of 634 U.S. multinational firms (1) confirm previously reported evidence that the disaggregation of the worldwide trade-weighted U.S. dollar exchange rate index into seven region-specific trade-weighted indices increases the precision and significance of exposure estimates; (2) show that models assuming that changes in spot exchange rates are unanticipated are frequently misspecified and, thus, unable to correctly detect the impact of currency movements on firm value; (3) reveal that forward and survey expectations enable us to distinguish between the effect of ‘realized’ and ‘unexpected’ currency movements; and (4) reveal that investors making pricing and hedging decisions prefer to use the information contained in short-term forward and survey expectation rates to the information included in long-term forecasts.  相似文献   
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