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Theoretical and Applied Climatology - This study seeks to investigate the effect of topographic (slope, elevation, and aspect) and climatic (precipitation and temperature) factors on vegetation in...  相似文献   
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The French government has committed to launch the satellite TARANIS to study transient coupling processes between the Earth’s atmosphere and near-Earth space. The prime objective of TARANIS is to detect energetic charged particles and hard radiation emanating from thunderclouds. The British Nobel prize winner C.T.R. Wilson predicted lightning discharges from the top of thunderclouds into space almost a century ago. However, new experiments have only recently confirmed energetic discharge processes which transfer energy from the top of thunderclouds into the upper atmosphere and near-Earth space; they are now denoted as transient luminous events, terrestrial gamma-ray flashes and relativistic electron beams. This meeting report builds on the current state of scientific knowledge on the physics of plasmas in the laboratory and naturally occurring plasmas in the Earth’s atmosphere to propose areas of future research. The report specifically reflects presentations delivered by the members of a novel Franco-British collaboration during a meeting at the French Embassy in London held in November 2011. The scientific subjects of the report tackle ionization processes leading to electrical discharge processes, observations of transient luminous events, electromagnetic emissions, energetic charged particles and their impact on the Earth’s atmosphere. The importance of future research in this area for science and society, and towards spacecraft protection, is emphasized.  相似文献   
3.
Detailed observations of the solar system planets reveal a wide variety of local atmospheric conditions. Astronomical observations have revealed a variety of extrasolar planets none of which resembles any of the solar system planets in full. Instead, the most massive amongst the extrasolar planets, the gas giants, appear very similar to the class of (young) brown dwarfs which are amongst the oldest objects in the Universe. Despite this diversity, solar system planets, extrasolar planets and brown dwarfs have broadly similar global temperatures between 300 and 2500 K. In consequence, clouds of different chemical species form in their atmospheres. While the details of these clouds differ, the fundamental physical processes are the same. Further to this, all these objects were observed to produce radio and X-ray emissions. While both kinds of radiation are well studied on Earth and to a lesser extent on the solar system planets, the occurrence of emissions that potentially originate from accelerated electrons on brown dwarfs, extrasolar planets and protoplanetary disks is not well understood yet. This paper offers an interdisciplinary view on electrification processes and their feedback on their hosting environment in meteorology, volcanology, planetology and research on extrasolar planets and planet formation.  相似文献   
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The recently completed prototyping efforts for a new type of riometer, the Advanced Rio-Imaging Experiment in Scandinavia (ARIES), required the development of a uniquely flexible software architecture to deal with what in software engineering terms is referred to as a ‘Wicked System:’ Source, volume and type of data as well as required processing are only very loosely defined at the outset of the project. Speed, reconfigurability, remote control and data provenance are of major importance for the success of the project both during development and during operation of the deployed prototype. Details of the Advanced Riometer Components (ARCOM) component-based software architecture are presented. The software architecture is not specific to ARIES, and ARCOM components can readily be re-used in other, similar instruments.  相似文献   
5.
Mountains are an excellent system for evaluating ecological and biogeographical patterns. The obvious variations of the environmental factors along the altitude create different zones with adapted plant assemblages. However, few studies make use of plant functional type(PFT) for describing the variation of vegetation along altitudinal gradients. A PFT is a group of taxa with similar traits which respond similarly to the environmental gradients. In this study, we used PFTs as indicators describing five vegetation zones in the western Alborz Mt, Iran from 2000 – 4500 m. The plant trait data presented here covers six plant traits including growth form, stemleaf ratio, spinescence, hairiness, leaf consistency and plant height of 297 species. We considered altitude and soil factors to test the importance of environmental variables. We applied a multivariate analysis of three table ordination, i.e. environmental, species, and traits data to identify the PFTs. We further applied fourth-corner statistic to quantify trait-environment relationships. A constrained hierarchical clustering was used to detect five altitudinal zones and two zones of low and high nitrogen concentration. With regard to altitude wediscuss the distribution of species, traits and PFTs. Growth form, plant height and stem-leaf ratio were significantly related to altitude and nitrogen. We identified 19 PFTs from which 18 were significantly associated to one or more altitudinal zones. While the lower altitudinal zones contain a variety of PFTs higher altitudes contain less PFTs with the highest altitude containing only one single PFT, tiny rosette plants with soft mesomorphic leaves. We identified grazing and climatic harshness as well as rockiness as the most important drivers of the distribution of plant functional traits and types across the studied gradient.  相似文献   
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The mantle sources of Tethyan basalts and gabbros from Iran,Tibet, the eastern Himalayas, the seafloor off Australia, andpossibly Albania were isotopically similar to those of present-dayIndian Ocean ridges and hotspots. Alteration-resistant incompatibleelement compositions of many samples resemble those of ocean-ridgebasalts, although ocean-island-like compositions are also present.Indian-Ocean-type mantle was widespread beneath the Neotethysin the Jurassic and Early Cretaceous, and present beneath atleast parts of the Paleotethys as long ago as the Early Carboniferous.The mantle beneath the Indian Ocean today thus may be largely‘inherited’ Tethyan mantle. Although some of theTethyan rocks may have formed in intra-oceanic back-arcs orfore-arcs, contamination of the asthenosphere by material subductedshortly before magmatism cannot be a general explanation fortheir Indian-Ocean-ridge-like low-206Pb/204Pb signatures. Supplyof low-206Pb/204Pb material to the asthenosphere via plumesis not supported by either present-day Indian Ocean hotspotsor the ocean-island-like Tethyan rocks. Old continental lowercrust or lithospheric mantle, including accreted, little-dehydratedmarine sedimentary material, provides a potential low-206Pb/204Pbreservoir only if sufficient amounts of such material can beintroduced into the asthenosphere over time. Anciently subductedmarine sediment is a possible low-206Pb/204Pb source only ifthe large increase of U/Pb that occurs during subduction-relateddewatering is somehow avoided. Fluxing of low-U/Pb fluids directlyinto the asthenosphere during ancient dewatering and introductionof ancient pyroxenitic lower-crustal restite or basaltic lower-arccrust into the asthenosphere provide two other means of creatingTethyan–Indian Ocean mantle, but these mechanisms, too,have potentially significant problems. KEY WORDS: Indian Ocean; mantle geochemical domains; ophiolites; Tethyan Ocean  相似文献   
7.
The prospects of the Clean Development Mechanism (CDM) and for carbon income, up to and beyond 2012, in the industrial sectors of Iran and five other Asian countries are investigated. The attractiveness and suitability of each host country, the status of their industrial sectors (based on four post-2012 scenarios), and the post-2012 potential of the CDM (or similar carbon projects) in these sectors are all examined. A multi-criteria analysis of Iran, Saudi Arabia, the UAE, Qatar, China, and India, based on seven sets of criteria (institutional, regulatory, economic, political, social, CDM experience, and energy production/consumption), is conducted, and the post-2012 potential carbon incomes of each country – based on CO2e emissions of industrial processes – are calculated. Finally, the Iranian industrial sector and the impact of deregulation of energy prices are examined. The post-2012 potential savings in the Iranian industrial sector are calculated based on energy savings, carbon income, and environmental savings. The results indicate that there is strong demand for investment and new technology in this sector to combat several-fold energy price increases. Moreover, high-priced carbon credits could play a meaningful role in post-2012 energy policies in this sector.

Policy relevance

This research is the first study to quantify the carbon market potentials in the industrial sectors of the selected Organization of the Petroleum Exporting Countries (OPEC) members. The Kyoto Protocol is considered by most OPEC countries to be a mixed bag of threats and opportunities and they have shown ambivalence towards it, mainly due to the threat a reduction of fossil fuel consumption poses to their economies. On the other hand, energy efficiency is a desirable goal for their industrial sectors. Iran, as an OPEC member country with vast energy resources, has mostly ignored the CDM during the first commitment period of the Kyoto Protocol and has performed poorly on CDM implementation. However, the current deregulation of energy prices in Iran, with profound cuts in energy subsidies, would definitely alter the perspective of its industrial decision makers on the post-2012 carbon potentials.  相似文献   
8.
Small-scale irregularities in the background electron density of the ionosphere can cause rapid fluctuations in the amplitude and phase of radio signals passing through it. These rapid fluctuations are known as scintillation and can cause a Global Positioning System (GPS) receiver to lose lock on a signal. This could compromise the integrity of a safety of life system based on GPS, operating in auroral regions. In this paper, the relationship between the loss of lock on GPS signals and ionospheric scintillation in auroral regions is explored. The period from 8 to 14 November 2004 is selected for this study, as it includes both geomagnetically quiet and disturbed conditions. Phase and amplitude scintillation are measured by GPS receivers located at three sites in Northern Scandinavia, and correlated with losses of signal lock in receivers at varying distances from the scintillation receivers. Local multi-path effects are screened out by rejection of low-elevation data from the analysis. The results indicate that losses of lock are more closely related to rapid fluctuations in the phase rather than the amplitude of the received signal. This supports the idea, suggested by Humphreys et al. (2005) (performance of GPS carrier tracking loops during ionospheric scintillations. Proceedings Internationsl Ionospheric Effects Symposium 3–5 May 2005), that a wide loop bandwidth may be preferred for receivers operating at auroral latitudes. Evidence from the Imaging Riometer for Ionospheric Studies (IRIS) appears to suggest that, for this particular storm, precipitation of particles in the D/E regions may be the mechanism that drives the rapid phase fluctuations in the signal.
Robert W. MeggsEmail:
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9.
This paper considers controlling and maximizing the absorbed power of wave energy converters for irregular waves. With respect to physical constraints of the system, a model predictive control is applied. Irregular waves’ behavior is predicted by Kalman filter method. Owing to the great influence of controller parameters on the absorbed power, these parameters are optimized by imperialist competitive algorithm. The results illustrate the method’s efficiency in maximizing the extracted power in the presence of unknown excitation force which should be predicted by Kalman filter.  相似文献   
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