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81.
西部欠发达地区报纸的生存竞争与发达地区一样正变得日益激烈。在这种生存竞争中,广告市场是决胜的最重要战场之一,因此培育和开拓广告市场就成为竞争取胜的重要砝码。本文特选择《西部商报》为个案,通过对其广告市场及其培育的现状、问题与对策的研究,试图为西北欠发达地区都市类报纸广告市场培育与开拓提供一定启示。  相似文献   
82.
Particle flux data were obtained from one instrumented array moored under the direct influence of the Almeria-Oran Front (AOF) in the Eastern Alboran Sea, Western Mediterranean Sea, within the frame of the “Mediterranean Targeted Project II-MAss Transfer and Ecosystem Response” (MTPII-MATER) EU-funded research project. The mooring line was deployed from July 1997 to May 1998, and was equipped with three sequential sampling sediment trap-current meter pairs at 645, 1170 and 2210 m (30 m above the seafloor). The settling material was analysed to obtain total mass, organic carbon, opal, calcium carbonate and lithogenic fluxes. Qualitative analyses of SST and SeaWiFS images allowed monitoring the location and development of the Western and Eastern Alboran Sea gyres and associated frontal systems to determine their influence on particle fluxes.Particle flux time series obtained at the three depths showed a downward decrease of the time-weighed total mass flux annual means, thus illustrating the role of pelagic particle settling. The total mass flux was dominated by the lithogenic fraction followed by calcium carbonate, opal and organic carbon. The time series at the various depths were rather similar, with two strong synchronous biogenic peaks (up to 98 mg m−2 day−1 of organic carbon and 156 mg m−2 day−1 of opal) recorded in July 1997 and May 1998. Through comparing the fluctuations of the lithogenic and calcium carbonate-rich fluxes with the biogenic flux, we observed that the non-biogenic fluxes remained roughly constant, while the biogenic flux responded strongly to seasonal variations throughout the water column.Overall, the temporal variability of particle fluxes appeared to be linked to the evolution of several tens of kilometres in length sea surface hydrological structures and circulation of the Alboran Sea. Periodic southeastward advective displacements of waters from upwelling events off the southern Spanish coast were observed on SST and SeaWiFS images. In between these periods, widespread phytoplankton blooms were observed. The influence of the varying surface structures resulted in changes in the biogenic particle flux. For example, we observed an opal pulse in April 1998 that resulted from a diatom-rich highly productive frontal surface situation above the mooring line.Estimation of the annual organic carbon export and calculation of a seasonality index indicate that the overall dynamics of the carbon reservoir within the Eastern Alboran Sea appears to be strongly influenced by the sea surface hydrological structures.  相似文献   
83.
文章在分析西部山区高速公路景观建设现状的基础上,对景观规划的基本原则和主要内容进行了阐述,提出将西部高速公路景观划分为城市风光、地域文化风光、田园风光及自然生态风光等四个区段,并结合实例对各区段景观规划特点进行了探讨。  相似文献   
84.
随着铁路市场投资主体的不断多元化,当新建线路引入既有车站,当两者主权不一时,如何有效整合两者资源,成为一个新的课题。以蒙西至华中地区煤运通道引入新余地区为例,通过对整合前方案、整合必要性、整合设计原则等方面进行研究,提出两大整合方案,并从运输组织、配套设施利用、通行能力、对既有生产组织影响、工程造价等多个方面对两方案进行对比,得出最佳方案。  相似文献   
85.
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   
86.
Although setback zones and lines are considered as a powerful coastal zone management tool ensuring public access, protecting the coastal ecosystem and minimizing natural hazards over developments, the lack of a solid and objective Mediterranean methodological framework for coastal setbacks demarcation appears profound. Especially for countries like Greece, this deficiency leads to long legal disputes encouraging illegal construction on the coastline. In this article a methodology on coastal setbacks demarcation over rocky, impermeable shores is proposed, followed, and implemented along a Greek shoreline, serving as a pilot case study. The methodology is consistent with the requirements of the integrated coastal zone management (ICZM) Protocol and the Greek legislation (L. 2971/2001), aiming to determine the “highest winter waterline,” accounting for the tidal and storm surge effects, the sea-level rise due to climate change impact, the extreme offshore wind and wave analysis, and the maximum potential wave run-up. Such a tool may bridge the gap between legislative provisions and actual ICZM Protocol implementation improving regional coastal management and planning.  相似文献   
87.
The Spanish Strategy for Coastal Sustainability (SCS) was an initiative aimed at implementing coastal interventions under the principles of Integrated Coastal Zone Management (ICZM) and improving the state of the coast at the Spanish national level. The SCS, promoted by the Spanish Ministry of the Environment, started as a broad national strategy in 2005 and was finally delivered as a coastal planning instrument at the regional level in late 2007, designed to address coastal policies within the Spanish maritime–terrestrial public domain (MTPD). The initiative was triggered by the increasing pressure on the coastal zone and its preparation was supported by different European initiatives, first of all the European Recommendation on ICZM (413/2002/EC), while taking into consideration the future requirements of the Mediterranean Protocol on ICZM of the Barcelona Convention, signed in February 2008. Technically, the preparation of the SCS included four steps: (i) a Stakeholder Identification and Engagement process, including a stocktaking of the laws and regulations, (ii) the design of a broad Strategic Framework for the Spanish coastal zone, including a set of specific objectives and the instruments for its implementation, (iii) the signature of cooperation agreements for ICZM between the central government and the regions, and (iv) a detailed Technical Diagnosis at the local scale, designed to address future coastal interventions in the maritime–terrestrial public domain and its areas of influence. This article aims to: (i) illustrate the triggering factors of the SCS, including the Spanish coastal issues, the administrative framework at the national level, and the European and international policies addressing coastal management and (ii) illustrate the approaches and methodologies used for the preparation of the SCS, reporting the most relevant quantitative results. The article concludes that the SCS gave a strong contribution in the construction of a base of knowledge for the coastal zone and to improve coastal management practices. Despite this, complex distributions of competences still undermine the implementation of strategic interventions. In this context, the future ratification of the ICZM Protocol of the Barcelona Convention represents an opportunity to use the SCS process results and improve coastal management practices and the state of the coast.  相似文献   
88.
王芳 《交通标准化》2013,(23):35-39
就中国西部旱区生态景观敏感的特殊性,以宁夏黄河金岸滨河大道(银川段)114km的工程为例,应用GooSeEarth、GETScreen和Auto CAD等相关软件对公路沿线景观格局进行数据采样.在此基础上,对其景观格局用地指标、景观破碎度和景观形状指数等相关指标进行分析,确定公路建设对旱区景观格局的影响方式,并指出公路方案设计是决定公路建筑物影响景观格局的关键阶段,提出旱区公路设计应遵循的基本原则.  相似文献   
89.
在介绍国内高速公路运营技术与管理水平的基础上,探讨近年来国内外新研发或者相对成熟的高速公路运营管理方面的新思路、新技术以及新技术设备,并与西部高速公路当前运营管理现状以及存在的问题相结合进行分析.提出与其相适应的管理模式和技术手段。  相似文献   
90.
The biological production characteristics of the Rhodes and western Ionian basins of the eastern Mediterranean are studied by a one-dimensional, coupled physical–biological model. The biological model involves single aggregated compartments of phytoplankton, zooplankton, detritus as well as ammonium and nitrate forms of the inorganic nitrogen. It interacts with the physical model through the vertical eddy diffusivity which is calculated using the Mellor–Yamada level 2.5 turbulence parameterization. The model simulations demonstrate the importance of the contrasting physical oceanographic characteristics of these two basins on affecting their yearly planktonic structures. The annual primary production in the Rhodes basin is estimated as 97 g C m2 yr−1 which is comparable with the northwestern Mediterranean. The western Ionian basin, on the contrary, possesses only 10% of the Rhodes' productivity and therefore represent a most oligotrophic site in the eastern Mediterranean. The Rhodes basin reveals a strong bloom in early spring, typically in March, a weaker bloom in early winter, typically in January, and a subsurface production below the seasonal thermocline during summer. This structure is slightly modified in the western Ionian basin, and the early winter and early spring blooms are merged to cover the entire winter. These results are supported favorably by the available observations both in their magnitudes and timing.  相似文献   
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