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31.
The risk and prevention of autoignition in underground coal storage facilities are reviewed in the light of the recent incidents of smouldering fires. Also, the opportunities are considered on the efficiency of the alternatives to prevent and extinguish closed-space fires. The complexities in avoiding and extinguishing underground fires are highlighted in the case example, describing the observations and outcome of a smouldering coal fire in the storage. The principles of self-heating and most critical factors in spontaneous combustion such as the condition and quality of coal are fairly well known, but usually only provide partial help in fire prevention. The documented cases and the case example suggest that nitrogen injection can be useful for extinguishing controllable fires. Three-phase foams and oxygen-displacing exhaust gases appear preferable against uncontrolled fires, particularly if access to the fire area is limited or impossible. Otherwise, efficient fire extinction during power plant operation can be challenging, as any air ingress tends to feed the fire and results in losses of the extinguishing agent and the heating value of coal. Methods and indicators for detecting and predicting the ignition are discussed, and improvements are suggested to enhance the storage and plant availability.  相似文献   
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This study investigates why financial markets react to the release of some economic indicators while ignoring others with similar informational content. Based on a Bayesian learning model, we show that the market impact of an economic indicator depends crucially on its early availability. The sequential introduction of the two largest German business surveys provides a natural experiment by which the model's implications are tested empirically. We show that even a large and well‐established indicator loses market impact if a similar indicator is launched and released earlier. © 2009 Wiley Periodicals, Inc. Jrl Fut Mark 30:909–937, 2010  相似文献   
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This study investigates the impact of international competitiveness on net employment, job creation, job destruction, and gross job flows for a representative sample of German establishments from 1993 to 2005. We find a statistically significant but economically small effect of real exchange rate shocks on employment, comparable to the one found in studies for the United States. However, contrary to the United States, the employment adjustment (among surviving firms) operates mainly through the job creation rather than the job destruction rate. Job destruction occurs essentially through discrete events such as restructuring, outsourcing and bankruptcy. We suggest that these findings are consistent with a highly regulated labor market, in which smooth adjustment is costly and possibly delayed.  相似文献   
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The Criterions of insurance companies in Germany are changing as consequences of market competition and regulation. Trends of differentiation follow former trends of assimilation. A modern typology of direct insurers resp. groups of insurers is less oriented by legal form of companies, more by targets of activities and stakeholder situation. In case of mutual companies there are effects of demutualization.  相似文献   
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In a general equilibrium model of the world economy, we develop a two-dimensional energy balance climate model featuring heat diffusion and anthropogenic forcing driven by global fossil fuel use across the sphere of the Earth. This introduces an endogenous location dependent temperature function, driving spatial characteristics, in terms of location dependent damages resulting from local temperature anomalies into the standard climate-economy framework. We solve the social planner's problem and characterize the competitive equilibrium for two polar cases differentiated by the degree of market integration. We define optimal taxes on fossil fuel use and how they may implement the planning solution. Our results suggest that if the implementation of international transfers across latitudes is not possible then optimal taxes are in general spatially non-homogeneous and may be lower at poorer latitudes. The degree of spatial differentiation of optimal taxes depends on heat transportation. By employing the properties of the spatial model, we show by numerical simulations how the impact of thermal transport across latitudes on welfare can be studied.  相似文献   
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This article discusses the innovations that have occurred in information technologies, which have led to the development of ‘intelligent’ electronics- based systems such as robots and computer-controlled tools. The author analyses the debate that has arisen surrounding the production and use of these systems, relating them to employment levels. He considers the future of industry and the economy, which will both see great changes in their structure as intelligent machines become ubiquitous.  相似文献   
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