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Cristina Mata Israel Hervás Jesús Herranz Juan E. Malo Francisco Suárez 《Transportation Research Part D: Transport and Environment》2009,14(7):447-452
Multiple factors determine the use and effectiveness of wildlife passages and crossings installed in new roads as mitigation measures against the barrier effect. It is unknown whether factors such as seasonality determine the use of these structures. This analyses the seasonality of structure used by vertebrates. Forty-eight transverse structures crossing the A-52 motorway in north-western Spain are studied during the summer and winter of 2002–03. The use of structures by terrestrial vertebrates was monitored by tracks left in marble dust and photographic systems, and comparisons carried out by means of generalized lineal methods for count data. Structural factors mostly determined the differential use of passage types by species but seasonal changes were detected both in the intensity of use and in passage selection by some species. 相似文献
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The interurban DRAG-Spain model: The main factors of influence on road accidents in Spain 总被引:1,自引:0,他引:1
Francisco Aparicio Izquierdo Blanca Arenas Ramírez Eva Bernardos Rodríguez 《Research in Transportation Economics》2013
This paper presents the results of applying DRAG methodology to the identification of the main factors of influence on the number of injury and fatal accidents occurring on Spain’s interurban network. Nineteen independent variables have been included in the model grouped together under ten categories: exposure, infrastructure, weather, drivers, economic variables, vehicle stock, surveillance, speed and legislative measures. Highly interesting conclusions can be reached from the results on the basis of the different effects of a single variable on each of the accident types according to severity. The greatest influence revealed by the results is exposure, which together with inexperienced drivers, speed and an ageing vehicle stock, have a negative effect, while the increased surveillance on roads, the improvement in the technological features of vehicles and the proportion of high capacity networks have a positive effect, since the results obtained show a significant drop in accidents. 相似文献
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Literature has focused on studying port choice independently or as an element of a supply chain without considering the joint selection with the country of origin/destination of the imports/exports. However, the characteristics and location of a port may make it more attractive to mobilise more freight from/to some particular countries rather than others, making the port choice decision dependent on the country of origin/destination of the cargo. This article proposes advanced econometric models to evaluate simultaneously port choice and the country of origin/destination choice for Colombian imports and exports. Findings suggest that for imports and exports domestic freight rate is the most important variable for the joint choice process. Also, for exports, maritime transit time is more relevant than for imports, while for the frequency of shipping lines the opposite is true. The existence of a trade agreement and the gross domestic product per capita also have a significant influence on the election of a country for exports/imports. 相似文献