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121.
Jara-Díaz Sergio R. Martínez-Budría Eduardo Cortés Cristiín E Basso Leonardo 《Transportation》2002,29(4):419-437
A long run multioutput cost function for the infrastructure services of Spanish ports is estimated using 286 observations on 26 ports during 11 years. Cargo specific marginal costs and the degree of economies of scale and scope are calculated up to a port level. Results show that liquid bulk and non-containerised general cargo present the lowest and largest marginal cost, respectively. Increasing returns to scale are present in general and for each and every port. A scope analysis indicates that port specialisation is not appropriate from the viewpoint of infrastructure. 相似文献
122.
It is a fact that coastal zones in the Mediterranean are becoming progressively more seriously degraded. Instrumental to the phenomenon in Spain is the evident failure of the coastal management that the institutions have pursued for over three decades, both under the old, state-centralized model, and the new organizational model with the political division of land into autonomous regions. This failure can in part be explained not only by the inadequate tools the administration possesses to address the dynamism and complexity of the new economic activities that have sprung up along the coast, but also by incoherent sectoral policies. Finally, there has been no all-encompassing political strategy capable of dealing with coastal communities' demands for development and the need for the protection of ecosystems and their natural resources. All this has resulted not only in a deterioration of the area, but also in the discrediting of actions implemented by the institutions, and their plans and programs being perceived as an obstacle to economic development. 相似文献
123.
Amaya Alvarez-Ellacuria Alejandro Orfila Maitane Olabarrieta Luís Gómez-pujol Raúl Medina Joaquín Tintoré 《Coastal management》2013,41(6):569-584
A real-time beach hazard level associated with nearshore hydrodynamics is presented in this article. The suitability of the discussed alert system is illustrated via its application to fifteen beaches in the Balearic Islands (Western Mediterranean Sea) providing nearshore safety conditions for beach safety manager. The system provides daily forecasts of nearshore wave conditions using the deep water wave forecasts. The shallow water wave data (wave height, period, and direction) together with the morphology of the site (presence of bars, capes, beach type, etc.) are used to define a hazard level (low, medium, and high) associated with local conditions. The resulting hazard level is transmitted via SMS to lifeguards and local authorities for real-time beach management. The low computational cost of this system after the initial implementation and subsequent calibration results in a very suitable approach for beach management in order to mitigate risks related to local hydrodynamics. 相似文献
124.
高速铁路建设的最初目的是连接相距400~600 km的都市区.但是近年,都市地区的郊区及城市出现了一些边缘位置的高铁车站,距都市中心的距离约100 km.重点研究位于马德里(瓜达拉哈拉、塞戈维亚和托莱多)、伦敦(斯特拉特福德、艾贝斯费特和阿什福德)和巴黎(鲁瓦西—戴高乐、马恩河谷—谢西和马西)附近的9座外围高铁车站,分析它们对都市区及当地的影响,并提取对加利福尼亚州高速铁路项目可借鉴之处. 相似文献
125.
This paper presents an analysis of the image of seafarers in Spanish newspapers. This is done by a qualitative and quantitative analysis of the news published in six representative newspapers in the days following the shipwrecks of 24 oil tankers between 1976 and 2007. A total of 359 news items have been studied analysing the type of language used, its place in the pages of the newspapers, the comments of the journalists who wrote them, etc., arriving at the conclusion that seafarers have a bad image in the Spanish printed press. 相似文献
126.
Alfonso Cuevas Jiménez Jorge I. Euán Ávila Rodolfo Silva Casarín 《Coastal management》2016,44(4):333-349
Beach erosion can have important socioeconomic and environmental consequences, particularly in tropical regions where tourism is a significant source of income. Although caused by natural processes, erosion is often aggravated by disorderly anthropogenic modification of the coast and extreme events. In Yucatan, Mexico, increasing urban development and deficient coastal management strategies as well as hurricanes have affected beach stability. This has highlighted the need for adequate coastal planning and policies that ensure the protection of key coastal ecosystems, such as beaches and sand dunes. To address this, a methodology to classify the coast according to its vulnerability is presented in this work. This methodology assumes that morphological features are indicators of beach evolution and the processes driving it and that these can be associated with different levels of vulnerability. The features considered are beach width, dune vegetation, anthropogenic pressure, and shoreline orientation, which were analyzed through aerial images and a multicriteria evaluation. It was observed that the most vulnerable areas are found near the most developed parts of the coast, where narrow beaches with little dune vegetation dominate. It is expected that this index will be of use to coastal planners and decision makers, particularly in the identification of critical zones. 相似文献