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11.
Amartanshu Srivastava Suresh Pandian Elumalai Elluru Venkata Ramana Raju 《Arabian Journal of Geosciences》2018,11(6):120
The objective of the present study was to delineate temporal and spatial changes in the coal fire and land use/cover within Bastacolla area of Jharia coal field. Studying this variation helped to decipher interconnection among the dynamics of the coal fire and concomitant changes in land use/cover. The detection of coal fires during a span of 14 years along with transitioning land use/cover was cost-effective and enabled planning for management of coal resources and environment. Landsat series of satellite data of 2002, 2009, 2013, and 2016 were processed for generating land surface temperature profiles vis-a-vis classified land use/cover of the study area. A single cut-off temperature was derived for mapping of coal fires using land surface temperature profile from 2002 to 2016. The satellite images were classified using support vector machines, and for depicting land use/cover change, post-classification change detection was done. Classification accuracy obtained was excellent with kappa coefficient ranging from 0.897 for classified image of 2002 to 0.799 for classified image of 2016. Results revealed that coal fires had shifted to the central west part of the area. Furthermore, pockets of coal fire from northern and eastern part of the study area have diminished. OB dumps and coal quarry/coal dump may be attributed towards the spatial change in coal fire while; OB dumps showed connotation with the highest temperature zones. Ground verifications for temperature profiles and coal fires were carried out using thermal camera which enunciated good agreement with results. 相似文献
12.
P. S. N. Murthy 《Mathematical Geology》1989,21(4):443-461
This paper presents the results of disjunctive kriging applied to a supergene iron ore deposit of Bailadila Range of India. Disjunctive kriging is applied firstly to compare estimates of the blocks by ordinary kriging and secondly to estimate benchwise local recoverable reserves of the orebody. Good agreement exists between block estimates by ordinary kriging and disjunctive kriging except for peripheral blocks with less borehole information. Estimation of benchwise reserves shows that the behavior of the distribution of grades is different in various benches. The study shows that disjunctive kriging can be applied successfully for estimation of local recoverable reserves in the case of a good grade hematite iron ore deposit. 相似文献
13.
S. K. G. Krishnamacharyulu Bh. V. V. Gopalarao I. V. Radhakrishna Murthy 《Pure and Applied Geophysics》1990,132(4):719-731
Magnetic anomaly profiles over two thin sheets separated by a small distance resemble those of dykes andvice versa. Interpretation of anomalies over a pair of sheets based on the magnetic properties of dykes predicts a dyke whose centre lies midway between the positions of the sheets. The dyke, on the other hand, is magnetically equivalent to a pair of sheets, both lying at the same depth and having the same magnetization.The magnetic anomalies due to a pair of sheets can be interpreted by framing linear equations between the anomalies and their distances measured from an arbitrary reference. Application of this method to anomalies of dipping sheets with a finite depth extent is indicated. 相似文献
14.
G.S. Murthy 《Physics of the Earth and Planetary Interiors》1985,39(2):89-107
Paleomagnetic studies have been made of certain constituents of the Bay St. George sub-basin. Specifically, results are reported from the Spout Falls Formation (Tournaisian), the Jeffreys Village Member of the Robinsons River Formation (Visean), and the Searston Formation (Namurian-Westphalian). The following magnetizations have been isolated: Spout Falls A (Tournaisian) with D = 343.5°, I = ?22.7°, k = 61.2, α95 = 7.1° and the corresponding pole at 28.6°N, 139.5°E (4.5°, 8.5°); Spout Falls B (Kiaman) with D = 166.7°, I = 12.2°, k = 51.7, α95 = 10.7° and the corresponding pole at 34.5°S, 42.7°W (5.5°, 10.9°); Jeffreys Village A (Visean) with D = 351.2°, I = ?27.3°, k = 54.0, α95 = 7.6° and the corresponding pole at 26.5°N, 130.7°E (4.5°, 8.3°); Searston A (Namurian) with D = 161.7°, I = 11.7°, k = 107, α95 = 7.4° and the corresponding pole at 33.9°S, 37.2°W (3.8°, 7.5°); and Searston C with D = 111.6°, I = ?13.8°, k = 28.8, α95 = 14.5° and the corresponding pole at 19.6°S, 19.0°E (7.6°, 14.8°). After comparison with paleopoles of similar ages derived from eastern and western Newfoundland rocks, from constituents of the east coast basin and for interior North America, it is concluded that: (1) it is unlikely that any large scale relative motion took place since the Early Carboniferous between eastern and western Newfoundland; (2) it is unlikely that any north-south relative motion took place between the east coast basin and the Bay St. George sub-basin; and (3) the Bay St. George sub-basin results do not support the earlier proposed displaced terrane hypothesis of the northern Appalachians in as much as the motions during the Carboniferous are not supported. There is evidence of the northward motion of the Appalachians and North America as a whole during the Carboniferous. The magnetostratigraphic horizon marker in the Carboniferous separating a dominant normal and reversed magnetization on the older side and an entirely reversed (Kiaman) magnetization on the younger side may be placed in the Bay St. George sub-basin at the base of the Searston Formation. 相似文献
15.
S. Sudnakar P. H. V. Vasudeva Rao Y. V. N. Krishna Murthy R. V. Rama Rao 《Journal of the Indian Society of Remote Sensing》1986,14(2):1-8
The study deals with the application of Remote Sensing for delineating various vegetation types along the three coastal districts of Andhra Pradesh. The satellite imagery of the region is divided into three types depending upon tone and texture. Each type is correlated with the ground truth. The species composition has been given and discussed. 相似文献
16.
J. Venkata Ratnam D. R. Sikka Akshara Kaginalkar Amit Kesarkar N. Jyothi Sudipta Banerjee 《Pure and Applied Geophysics》2007,164(8-9):1641-1665
As a part of the Experimental Extended Range Monsoon Prediction Experiment, ensemble mode seasonal runs for the monsoon season
of 2005 were made using the National Centre for Environmental Prediction (NCEP), T170L42 AGCM. The seasonal runs were made
using six initial atmospheric conditions based on the NCEP operational analysis and with forecast monthly sea-surface temperature
(SST) of the NCEP Coupled forecast system (CFS). These simulations were carried out on the PARAM Padma supercomputer of Centre
for Development of Advanced Computing (C-DAC), India. The model climatology was prepared by integrating the model for ten
years using climatological SST as the lower boundary. The climatology of the model compares well with the observed, in terms
of the spatial distribution of rainfall over the Indian land mass. The model-simulated rainfall compares well with the Tropical
Rainfall Measuring Mission (TRMM) estimates for the 2005 monsoon season. Compared to the model climatology (7.81 mm/day),
the model had simulated a normal rainfall (7.75 mm/day) for the year 2005 which is in agreement with the observations (99%
of long-term mean). However, the model could not capture the observed increase in September rainfall from that of a low value
in August 2005. The circulation patterns simulated by the model are also comparable to the observed patterns. The ensemble
mean onset is found to be nearer to the observed onset date within one pentad. 相似文献
17.
Ndr Krishna A K Maji YVN Krishna Murthy BSP Rao 《Journal of the Indian Society of Remote Sensing》2001,29(3):107-113
Availability of remote sensing data from earth observation satellites has made it convenient to map and monitor land use/land cover at regional to local scales. A land cover map is very critical for a various planning activities including watershed planning. The spectral and spatial resolutions are major constraints for mapping the crop resources at microlevel. The cropping pattern zones have been mapped using the false color composite, physiography, irrigation and toposheets. The IRS LISS-III data is classified into various categories depending on spectral reflectance from crop canopy and are overlaid on cropping zones map. The re-classified resultant map provides land use/land cover information including dominant cropping systems. The canopy cover is estimated monthly considering the crop calendar for the area. 相似文献
18.
The time series BT profiles and surface winds and atmospheric pressure, collected in the deep waters off Ratnagiri and Karwar
during summer monsoon were utilized to document the characteristics of internal waves (IW). Low-frequency (≤2, cycle per day
(cpd)) IW off Ratnagiri are found to propagate at 83 cm/s with wavelengths of 45 km and wave heights upto 40 m. These parameters
for high-frequency (>2 cpd) IW off Karwar correspond to 99 cm/s, 3 km and 23 m. The IW off Karwar appear to leave the station
at 70° (±10°) (measured from the horizontal). The data sets were further analysed to address the harmonic composition of the
IW and identify the possible sources for the observed IW fields. Power spectra of the IW indicated energy peaks at inertial
(0·6 cpd) and tidal (1 and 2 cpd) frequencies off Ratnagiri and in the high-frequency band of 0·5–2·0 cycles per hour off
Karwar. The coherence between the IW and wind/tide is found to be good at several frequencies within the IW spectrum. This
feature probably suggests tides as a source for the IW of tidal frequencies and winds and tides as a joint source for the
IW at the remaining frequencies. 相似文献
19.
S. N. Murthy 《Pure and Applied Geophysics》1970,81(1):91-100
Summary The propagation of Love waves under the influence of an externally applied magnetic field is studied. The general phase velocity equation is derived and two special cases when the magnetic field is aligned with and transverse to the direction of wave propagation are discussed. in these cases, it is found that the magneto-elastic problem in hand can be reduced to the corresponding problem in pure elasticity. 相似文献
20.
B. S. R. Rao I. V. Radhakrishna Murthy C. Visweswara Rao 《Pure and Applied Geophysics》1973,110(1):2056-2065
Summary A common computer program for the interpretation of vertical magnetic anomalies of spheres and horizontal cylinders has been developed. The input consists of the observed anomalies noted against their distances measured from an arbitrary point in the profile and a code number for each model. The program is written so that the positions and magnitudes of the maximum and minimum anomalies are located and their ratios and signs are used to define the initial parameters of the model under consideration. The errors resulting from these approximate values are derived and are solved for the increments to be given to the initial values. The process is repeated until the sum of the squares of the errors is less than 0.25% of the sum of the squares of the observed anomalies. The method has been tested on various theoretical examples and the results justify the validity of the programme. 相似文献