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991.
In the last two decades, many states established rail promotion programs in an effort to limit the contraction of their railroad networks. Now federal funds for rail projects are nearly exhausted, and states must decide whether to expand considerably their levels of internal funding for short line investments. Such a decision requires a careful articulation of policy goals, combined with sound cost-benefit techniques. Research shows, however, that states often fail to evaluate the full range of costs and benefits when considering rail investments. Instead, the economic development benefits of local rail service frequently are overstated, while the potential for rail investments to meet broader transportation planning needs is neglected. This paper evaluates the rationale behind state intervention in the rail industry, discusses the tendency of states to focus on economic development to the exclusion of other benefit categories, and presents summary results from an analysis of an investment project in North Carolina. The paper suggests that state funding for rail projects is more likely to be justified based on intermodal substitution benefits generated by local rail service, rather than the railroads' potential to increase jobs.  相似文献   
992.
There is no doubt that medical semiotics are having a revival at the moment. Different aspects of yesterday's and today's interest in semiotics and in the historical interpretation of signs of disease in the context of theory and history of medicine can be illuminated: their deciphering as the history of the sign in medicine by historic science, their overestimation by philosophy during the Age of Enlightenment, their reduction to a phenomenology of medicine and natural science during the first half of the 19th century and their transformation to medical diagnostics since the middle of the 19th century and recently even their functionalization as methodical instrument within the history of science. The following will show the change in meaning of medical semiotics. Modern development and especially the transition to medicine, based on natural science, will be emphasized.  相似文献   
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The characterization of the products of international cooperation as public goods has been severely challenged, undermining a central pillar of theories of international cooperation. I review the criticism of public goods assumptions, identifying the need to account for both exclusion and rival consumption in international cooperative arrangements. Drawing on the recent debate of states as relative versus absolute gains maximizers, I offer a characterization of international cooperative arrangements as discriminatory clubs. I develop a refined relative gains model, which focuses on relative net gains, and apply it to a hypothetical situation to illustrate its usefulness in predicting patterns of exclusion and distribution in international trade.  相似文献   
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The Campania was a fertile area, with a growing population during the eleventh and twelfth centuries, and was economically more advanced than most of the rest of southern Italy. This essay examines the impact of the Norman conquest of the south upon this region, with special reference to the settlement pattern and the aristocracy. It concludes that the role of incastellamento in changing the pattern of settlement was relatively limited, and the extensive incastellamento of the Montecassino lands (a product of Norman pressure upon the abbey) cannot be taken as typical. Furthermore, while the Norman conquest led to colonisation by French aristocrats, this did not entirely displace existing Lombard families, and widespread intermarriage led to a blurring of the distinction between Lombards and Normans. The impact of political crises during the twelfth century was also more limited than might be supposed, and continuity rather than change characterised the nobility of the Norman period.  相似文献   
1000.
We develop a new conceptual approach to locating inspection stations for hazardous vehicles, prevention, and compare it to the previous, punitive, philosophy of the flow-capturing location model. We implement this preventive protection philosophy with a new mixed integer program that maximizes hazard avoidance by locating a number of inspection stations to detect and remove hazardous vehicles as early in their trips as possible. We test the model's performance and analyze the spatial characteristics of solutions simulating several potential applications. Our computations demonstrate that a relaxed integer-linear program is overly demanding computationally and that a simple greedy heuristic lacks robustness. We suggest further approaches to developing more powerful and efficient solution methods.  相似文献   
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