全文获取类型
收费全文 | 55篇 |
免费 | 2篇 |
国内免费 | 2篇 |
专业分类
测绘学 | 7篇 |
大气科学 | 8篇 |
地球物理 | 14篇 |
地质学 | 23篇 |
天文学 | 3篇 |
综合类 | 2篇 |
自然地理 | 2篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 1篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 2篇 |
2015年 | 4篇 |
2014年 | 1篇 |
2013年 | 1篇 |
2012年 | 1篇 |
2011年 | 3篇 |
2010年 | 3篇 |
2009年 | 2篇 |
2008年 | 4篇 |
2006年 | 2篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 2篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1997年 | 1篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1987年 | 1篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1969年 | 1篇 |
排序方式: 共有59条查询结果,搜索用时 15 毫秒
31.
O. N. Dhar P. R. Rakhecha B. N. Mandal R. B. Sangam 《Pure and Applied Geophysics》1982,120(3):483-494
The rainstorm of 17 to 21 July 1981 which caused exceptionally heavy rains and floods in arid Rajasthan, was analysed. It was observed that 7 stations in the rainstorm area broke their previous 80-year record of one-day rainfall, and two of these stations equalled their respective estimates of probable maximum precipitation (PMP). A comparison of areal raindepths of this rainstorm with the similar raindepths of past severe-most rainstorms of this region showed that this rainstorm gave unprecedented raindepths up to about 38 850 sq. km (i.e. 15 000 sq. miles) for a 3-day duration. 相似文献
32.
Preparation of a generalized chart of probable maximum precipitation (PMP) for the southern half of the Indian peninsula lying between lat. 8°N to 16°N has been attempted in this study. Maximum 1-day rainfall data of 70 to 80 years from 1891 for about 600 stations in the peninsular states of Tamil Nadu, Kerala, South Karnataka and southern portions of Andhra Pradesh were used. In order to get appropriate values of PMP, envelope frequency factor (K m) curve based on the actual rainfall data of the region was prepared. This study has shown that one-day PMP estimates over this region range from about 25 cm to about 85 cm. The heavy rainfall received over the coastal areas of Tamil Nadu in association with the cyclonic disturbance of November 1976 was examined and it was found that this rainfall was nowhere near the PMP estimates for this area. 相似文献
33.
Sinkhole subsidence due to mining 总被引:2,自引:2,他引:2
This paper reviews the modes of formation of sinkhole subsidence associated with mining activities, drawing on examples in India. Sinkhole (pot-hole) subsidence is an abrupt local depression at the surface which can be hazardous to life and property due to its tendency to occur without warning. Shallow extraction, weak overburden and geological discontinuities are the main factors which cause them. Sinkholes occur due to the failure of a mine roof which migrates through the overlying strata until the failure zone intercepts the unconsolidated overburden. Alternatively they may occur by the creation of cavities in the overburden following the inflow of sand and soil from the overlying weathered and friable strata through faults. Overburden cavities eventually cave in and sinkholes appear at the surface. Sinkholing phenomena can be controlled to some extent by proper design of mining supports and construction of walls to create a barrier around an area prone to sinkholes in bord and pillar workings. Backfilling and grouting can be used to stabilize abandoned underground workings. 相似文献
34.
Manthira Moorthi Subbiah Debajyoti Dhar Sivakumar Ramamoorthy 《Journal of the Indian Society of Remote Sensing》2018,46(9):1527-1535
An automatic image registration approach is presented here can be used to register daily images of Indian geostationary satellite system INSAT-3D acquired every 30 min’ interval without use of any ground control points (GCPs). There is always a pressing need to register meteorological images that are acquired over earth from geostationary platforms every 15–30 min, covering almost one-third of the earth. Weather forecast activities include derivation of atmospheric motion vectors, which demand immediate processing of such images to a reasonable accuracy in terms of its relative location accuracy. Generally followed approaches make use of image navigation models and GCPs drawn from known landmarks in land ocean boundaries and correlate image features before estimating a transform to warp the current acquisition to a known geometry. However, the hierarchical (coarse to fine) approach explained here makes use of intensity based Mutual Information as a similarity measure from a population of pixels selected randomly and uses stochastic gradient descent optimizer to estimate an affine transform between registering image pair, delivers satisfactory results. 相似文献
35.
Ocean Dynamics - A fourth-order nonlinear evolution equation of interfacial progressive waves in two-layer fluids of finite depths is derived in the case when there is a depth uniform current in... 相似文献
36.
V. V. S. Gurunadha Rao R. L. Dhar T. Jayachand C. S. Khoker 《Environmental Geology》2000,39(10):1138-1146
Mathura oil refinery was commissioned during 1977 and effluent storage ponds were constructed at the same time. These storage
ponds receive wastewater from the refinery at a rate of 10000 m3/day. After treatment, waste water is discharged through a 3-km pipeline to a stream leading to the Yamuna river. The groundwater-monitoring
as well as water-quality monitoring was carried at 24 observation wells in the refinery site during 1997. The water quality
measurements indicated total dissolved chloride and sulphate concentration of native groundwater as 400 mg/l, whereas elevated
levels up to 600 mg/l were found at the wells close to polishing ponds. Thus combined transport of chloride and sulphate was
simulated in the mass transport model. A three-dimensional flow, pathlines and mass transport model of the aquifer system
were constructed to analyze the impact of seepage from polishing ponds contaminating the groundwater regime. The permeability
of aquifer varies between 1.5–2.5 m/day. The porosity of formation was assumed as 0.2. The constant head and constant concentration
boundaries were assigned to the nodes representing effluent storage ponds. Longitudinal dispersivity of 100 m, horizontal
transverse dispersivity of 10 m and vertical transverse dispersivity of 0.01 m were assumed. The mass transport model was
calibrated for 20 years by comparing total dissolved chloride and sulphate concentrations from 1997. The model predictions
indicate further migration of contaminants on the east of effluent ponds in future.
Received: 4 January 1999 · Accepted: 12 July 1999 相似文献
37.
Angelica glauca is one of the important medicinal plants and it is widely used by indigenous communities for different purposes. The present study analyzes variability in reproductive characters of A. glauca. The reproductive parts were found having significant positive correlation with altitude (e.g.,number of umbellets /umber r= 0.857,p〈0.05; umbel diameter r=0.735,p〈0.05). 相似文献
38.
39.
40.