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61.
62.
Although India has a long experience in ship-borne experiments and oceanographic instrumentation, the atmospheric component has not received much attention in the past. In this paper, the basis of the atmospheric instrumentation system assembled for use on board ORV Sagar Kanya for the BOBMEX-Pilot experiment is described along with some representative results. Wherever possible, Woods Hole's IMET recommendations for meteorological sensors for applications in the marine environment have been followed to keep our measurements in par with international standards. The sensors were tested during the BOBMEX-Pilot experiment and all sensors worked well. Velocity, humidity and temperature data have been successfully collected using fast sensors. It is shown that the component due to the ship's pitching motion can be removed from the measured vertical velocity by making use of an accelerometer. This makes it possible to calculate the surface fluxes by direct methods.  相似文献   
63.
Mass, radius and moment of inertia are direct probes of compositions and Equation of State (EoS) of dense matter in neutron star interior. These are computed for novel phases of dense matter involving hyperons and antikaon condensate and their observable consequences are discussed in this article. Furthermore, the relationship between moment of inertia and quadrupole moment is also explored.  相似文献   
64.
Response of the coastal regions of eastern Arabian Sea (AS) and Kavaratti Island lagoon in the AS to the tropical cyclonic storm `Phyan??, which developed in winter in the south-eastern AS and swept northward along the eastern AS during 9?C12 November 2009 until its landfall at the northwest coast of India, is examined based on in situ and satellite-derived measurements. Wind was predominantly south/south-westerly and the maximum wind speed (U10) of ~16 m/s occurred at Kavaratti Island region followed by ~8 m/s at Dwarka (Gujarat) and ~7 m/s at Diu (located south of Dwarka) as well as two southwest Indian coastal locations (Mangalore and Malpe). All other west Indian coastal sites recorded maximum wind speed of ~5?C6 m/s. Gust factor (i.e., gust-to-speed ratio) during peak storm event was highly variable with respect to topography, with steep hilly stations (Karwar and Ratnagiri) and proximate thick and tall vegetation-rich site (Kochi) exhibiting large values (~6), whereas Island station (Kavaratti) exhibiting ~1 (indicating consistently steady wind). Rainfall in association with Phyan was temporally scattered, with the highest 24-h accumulated precipitation (~60 mm) at Karwar and ~45 mm at several other west Indian coastal sites. Impact of Phyan on the west Indian coastal regions was manifested in terms of intensified significant waves (~2.2 m at Karwar and Panaji), sea surface cooling (~5°C at Calicut), and moderate surge (~50 cm at Verem, Goa). The surface waves were south-westerly and the peak wave period (T p) shortened from ~10?C17 s to ~5?C10 s during Phyan, indicating their transition from the long-period `swell?? to the short-period `sea??. Reduction in the spread of the mean wave period (T z) from ~5?C10 s to a steady period of ~6 s was another manifestation of the influence of the cyclone on the surface wave field. Several factors such as (1) water piling-up at the coast supported by south/south-westerly wind and seaward flow of the excess water in the rivers due to heavy rains, (2) reduction of piling-up at the coast, supported by the upstream penetration of seawater into the rivers, and (3) possible interaction of upstream flow with river run-off, together resulted in the observed moderate surge at the west Indian coast. Despite the intense wind forcing, Kavaratti Island lagoon experienced insignificantly weak surge (~7 cm) because of lack of river influx and absence of a sufficiently large land boundary required for the generation and sustenance of wave/wind-driven water mass piling-up at the land?Csea interface.  相似文献   
65.
The present study was conducted in Solan Forest Division of Himachal Pradesh covering an area of about 57,158 ha. The aim was to estimate and assess the temporal change in carbon stock of the Chil Working Circle, in two forest ranges of the Division, Solan and Dharampur, over the period of 1956-2011. The inventory data of the working plans of Solan Forest Division from 1956-1957, 1984-1985 and 2002- 2003 were used in the present study while field data for biomass estimation was collected for the year 2011. The results showed a declining trend in carbon stock over 1956-1984 period, however, an increasing trend over 1984-2002 was observed, which showed a further increase for the period 2002-2011. These fluctuating trends in the forest carbon stock can be related to increasing anthropogenic pressure on forests and the subsequent introduction of a ban on green felling envisaging efficient forest management, both of which affect the forest carbon pool significantly.  相似文献   
66.
The establishment of marine protected areas (MPA) has been a common government response to increasing fishing, tourism and other human activities that lead to decline in coral and marine resources. MPAs often suffer inadequacy of funds and simply become “paper parks”. This study makes a case for the feasibility of a self-financing mechanism for MPAs by estimating potential surplus benefit that recreational users may gain from MPAs in Jamaica. These same recreational users in turn, might be willing to pay a small portion of that gain toward the management costs. With the help of a travel cost model and the visitors’ willingness to pay (WTP) estimates, we show that the management costs of the park amount to a negligible amount; less than 0.1% of the annual total WTP. Furthermore, using these WTP estimates and the findings from other stakeholders’ surveys (hotels, tour operators, etc.), the paper provides insights on user-supported funding policies, such as taxes and fees, which might sustain the operations of MPAs in Jamaica and the broader Caribbean region.  相似文献   
67.
Bhat  Deepak R.  Bhandary  N. P.  Yatabe  R. 《Natural Hazards》2013,65(3):2161-2173
There are few places in the world to monitor aseismic creep. One of them is the Ismetpasa segment of the North Anatolian Fault. The observations in the Ismetpasa showed that the creep rate progressively decreased along the 40 years before the 1999 Kocaeli-Golcuk (Mw = 7.6) earthquake and then started increasing. This phenomenon might be a systematic of the creeping segments. If it is the case, this behavior can be utilized for early warning before the expected major earthquake in the Marmara Sea. In this study, the creep rate of the segment has been studied by GPS and InSAR technologies. The results showed that the rate has decreased to 1.3 cm a year. This result might be an indication of stress starting increase. If the segment retains the decreasing trend and it is ceased by a major earthquake, it would be a proof of the relationship between the creep process and the earthquakes. Then, the creep process might be utilized for early warning.  相似文献   
68.
The physicochemical properties and major ion chemistry of the groundwater sources from alluvial aquifers along the stretch (60 km) of Jhelum River in Kashmir Himalaya were determined in order to identify hydro-geochemical processes and their suitability for drinking purposes. The data depicted that calcium and bicarbonates were dominating among the cations and anions. The results indicate the trend of cation dominance as Ca2+ > Na+ > Mg2+ > K+, whereas anion dominance was in the order of HCO3 ? > Cl? > SO4 2?. Ratio of calcium to magnesium indicated the dissolution of Ca2+ from CaCO3, which results in an increased levels of Ca2+ in the groundwater. Interpretation of Piper Trilinear plot understands the various geochemical processes affecting the groundwater quality and shows groundwater was dominated by Ca–HCO3 type. The pH was recorded in the slightly alkalinity range 7.2–7.8 and was showing positive correlation with HCO3 ?. The chloro-alkaline indices revealed 86% of the sources exchange by a type of base-exchange reactions, rest by cation–anion exchange. Gibbs diagram revealed groundwater sources fall in the category of rock dominance. The concentration of the nitrogen compounds was in the progression of NO3–N > NH4–N > NO2–N, and the PO4 ? fluctuated from 0.12 to 0.22 mg/L. Moreover, corrosivity ratio indicated that water from the majority of sources (71%) is safe to supply using pipes without any corrosive effects, while 29% of sources are corrosive in nature and need non-corrosive pipes for transporting and lifting of groundwater. The results revealed, groundwater samples were within permissible limits as prescribed by International and National standards, for drinking purposes. The State government and NGO’s can show their interest in utilizing such water resources to overcome the shortage of drinking water in a sustainable way for the daily consumption of the people living in the vicinity of Jhelum River.  相似文献   
69.
The objective of the present study is to simulate the physical and socioeconomic factors of human vulnerability to tropical cyclones and storm surges at the household level in existing and changing status of households. The primary data were collected from a cyclone prone coastal area in Bangladesh, through structured questionnaire and GPS survey, key informants interviews and field observations. In order to simulate the physical and socioeconomic factors geographical information systems based Structured Query Language (SQL) query has been used. The study simulated the physical and socioeconomic factors of human vulnerability to tropical cyclones and storm surges on the basis of collected data through pre-designed SQL query. The study found the number of most vulnerable households under existing conditions and how much it will be afterward of a favourable or adverse change of the factors of vulnerability associated with households. The major findings of the study unveil that the socioeconomic and physical factors of human vulnerability have important function to determine the household’s level of vulnerability to the cyclone induced disaster. It has been demonstrated that the degree of vulnerability of households is changed with its physical and socioeconomic status. This study provides a conceptual model for assessing and simulating vulnerability to other natural hazards like floods, droughts, riverbank erosions and so forth. This study highlights that the households’ intrinsic vulnerable conditions are responsible for its defencelessness to the hazards and the reduction of vulnerability is the first measure of integrated and sustainable disaster management in the coastal Bangladesh.  相似文献   
70.
The spatial and angular distributions and also the energy spectrum of hard X-rays from solar flares have been studied in terms of the energy and angular distributions of the accelerated electron beam. The incident electron distributions as functions of column density have been computed by combining the analytical treatment of small-angle scattering with the Monte-Carlo calculations for large angle scattering. To start with monoenergetic electrons at 0°, 30°, and 60° incidence angles have been taken. Using the Bethe-Heitler total cross section and the Sauter differential cross section along with the calculated electron distributions, the bremsstrahlung flux and its angular distribution for different photon energies > 10 keV have been studied as function of column density. The shape of the calculated curves agrees with the observations of PVO/ISEE-3 lending support to the beamed thick-target model for X-ray generation with continuous injection.Physics Department, Vishwa Bharti Institution, Rainawari, Srinagar, India.  相似文献   
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