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As maritime processes do no stop at sea ports, hinterland operations have to be considered and addressed as well. This becomes obviously on designing and managing seamless cargo and information flows from/to hinterland regions via sea ports from/to transcontinental markets. Nowadays, also security-related aspects need to be tackled in order to enable continuous flows corresponding to security legislations and technical requirements set up in the field of maritime and intermodal hinterland transport. Ensuring transport security within the European transport market requires both adequate security legislations and innovative concepts. While for the maritime sector, including sea ports, security regulations are already in force, hinterland operations (road, rail and Inland Waterway Transport) are only indirectly affected today, either on carrying out transports from/to sea ports or exporting commodities to overseas territories. This results in the need for innovative security strategies and concepts combining maritime with hinterland transport enabling seamless security processes.  相似文献   
2.
Data from two cruises, one in April/May 1996 and one in December/January 1993, covering the same wide area in the offshore Weddell Sea, were used to derive the annual extent of entrainment and the capacity of the biological pump. The former property was obtained with the help of dissolved oxygen data, whereas the latter was approximated with nutrients. Especially the data from April/May, representing the initial state of the winter surface layer, were crucial to assess the annual extent of these processes. The results were applied to our carbon dioxide data. The annual increase of the Total CO2 (TCO2) concentration in the surface layer due to vertical transport amounts to 16.3 μmol kg−1. An entrainment rate of deep water in the surface layer amounting to 35±10 m yr−1 was deduced. The compensating, biologically mediated TCO2 reduction was calculated to be larger than the TCO2 increase due to vertical transport. Since the balance of these two processes determines whether the Weddell Sea is a source or a sink of CO2, this indicates that the Weddell Sea, albeit upwelling area, is definitely a sink for atmospheric CO2 on an annual basis. This conclusion is further supported by contemplations that the biological drawdown of CO2 in the Weddell Sea as a whole is probably underestimated by our calculations. The new production for the Weddell Sea on a per unit area basis was found to be much higher than that for the Antarctic Ocean, when the latter value is being obtained by traditional biological methods. On the other hand, the CO2 uptake by the Weddell Sea on a per unit area basis is somewhat smaller than the CO2 uptake by the world ocean.  相似文献   
3.
Tønnesen  Anders  Hagen  Oddrun Helen  Tennøy  Aud 《Transportation》2021,48(5):2263-2286
Transportation - In this paper, two public information campaigns were analysed. These were related to capacity reductions, caused by maintenance work, in two main road tunnels—at Smestad and...  相似文献   
4.
The winter St. Helena climate index and extreme Benguela upwelling   总被引:1,自引:0,他引:1  
Climate changes in the subtropical South-east Atlantic turn out to be well described by the St. Helena Island Climate Index (HIX) and observed fluctuations are in good agreement with inter-decadal variability of the entire South Atlantic Ocean. Year-to-year variations of the averaged austral winter HIX (July–September), representative of the main upwelling season, were compared with (i) corresponding averages of the geostrophic alongshore component of the south-east trade wind (SET) between St. Helena Island in the south-west and Luanda/Angola in the north-east, (ii) the meridional distribution of surface waters colder than 13 °C to characterise intense Benguela upwelling (IBU), and (iii) the meridional position of the Angola-Benguela Frontal Zone (ABFZ) determined by means of sea surface temperature images for offshore distances between 50 and 400 km. Temporal changes of these parameters were investigated and showed that the frequency of consecutive years of strong and relaxed Benguela upwelling is characterised by a quasi-cycle of about 11–14 years. It is proposed that the index of the winter HIX may be used as a ‘surveyor’s rod' to describe interannual changes in the Benguela upwelling regime as well as those of the embedded marine ecosystem.  相似文献   
5.
概述了欧盟铁路货运的发展趋势,并介绍了在几种新型货车上采用的新技术。  相似文献   
6.
Biogenic silica cycle in surface sediments of the Greenland Sea   总被引:2,自引:0,他引:2  
In contrast to several investigations of biogenic silica (BSi) content and recycling in surface sediments of the Southern Ocean, little is known about the benthic cycle of BSi in high northern latitudes. Therefore, we investigated the silicic acid concentration of pore water and BSi content of surface sediments from the Greenland Sea. Low BSi contents of less than 2% were observed. High-resolution (2–5 mm) BSi profiles and comparisons to trap studies suggest that only relatively dissolution-resistant siliceous components reach the seafloor. Pore water investigations reveal BSi fluxes of more than 300 mmol m−2 a−1 only for a few sites on the shelf. A statistically significant relationship between water depth and BSi rain rate reaching the seafloor was not observed. Sampling along a transect perpendicular to the marginal ice zone (MIZ) revealed no enhanced rain rate of BSi reaching the seafloor in the vicinity of the ice edge. Although the MIZ of the Greenland Sea is characterized by the enhanced export of biogenic particles from surface waters, this feature is not reflected in the benthic cycle of biogenic silica. The lack of such a relationship, which is in contrast to observations of shelf and continental margin sediments in the southern South Atlantic, is probably caused by the enhanced dissolution of BSi in the water column and highly dynamic ice conditions in the Greenland Sea.  相似文献   
7.
Copepods were sampled by a multiple opening-closing net in the eastern Weddell Sea during various seasons (late winter/early spring, summer, autumn). Total copepod biomass integrated over the upper 1000 m varied seasonally between 1.7 mg C m−3 in late winter/early spring and 3.7 mg C m−3 in autumn. After the dark season the copepods were rather evenly distributed vertically and highest biomass levels were found in the mid-water layers between about 200 m and 500 m. By contrast, especially in summer but also in autumn copepod biomass concentrated in the uppermost water layer. A total of 64 calanoid species were identified in the upper 1000 m with maximum species numbers in the deepest layer. The large calanoids Calanus propinquus, Calanoides acutus, Metridia gerlachei, Euchaeta antarctica and the small calanoid Microcalanus pygmaeus prevailed and accounted for 60–70% of total copepod biomass, while the small poecilostomatoid Oncaea and the cyclopoid Oithona species comprised about 20%. Hence, the distribution pattern of the entire copepod biomass is strongly influenced by the life cycles of a few dominant species.  相似文献   
8.
Economic assessment of universally designed transport projects has not been studied in depth in the transport planning literature. Universal Design (UD) refers to the design of transport systems in a way that they are accessible to all users, irrespective of the users’ abilities. This definition of UD has not yet gained roots in the transport economic literature. The conventional thinking is that UD is for the few, i.e., the impaired, and given that they are few in numbers, UD projects will generally be unprofitable from a socioeconomic point of view because benefits will be low while investment costs will be too high. The objective of this paper is to prove the opposite: UD projects benefit all users of the facility, whether impaired or not, and the additional costs of implementing them are generally low; hence, their net present values are high and positive. We build on collaborative work between the Norwegian Public Roads Administration (NPRA) and the Institute of Transport Economics (TOI) aimed at creating guidelines for assessing the economic merits of UD projects. Therefore, in this paper, we: (1) define how UD is to be understood in the context of road and public transport; (2) describe the types of benefits and costs that accrue to users if UD projects are implemented; (3) address how the benefits and cost can be valued in monetary terms; and (4) using three different types of projects, demonstrate that UD projects are surprisingly profitable from a socioeconomic point of view. Finally, we address the implications of our findings and explain why governments need to be concerned with UD of transport systems.  相似文献   
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