全文获取类型
收费全文 | 127篇 |
免费 | 2篇 |
国内免费 | 3篇 |
专业分类
测绘学 | 24篇 |
大气科学 | 7篇 |
地球物理 | 17篇 |
地质学 | 64篇 |
海洋学 | 8篇 |
天文学 | 11篇 |
自然地理 | 1篇 |
出版年
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 6篇 |
2017年 | 7篇 |
2016年 | 8篇 |
2015年 | 5篇 |
2014年 | 7篇 |
2013年 | 14篇 |
2012年 | 8篇 |
2011年 | 8篇 |
2010年 | 4篇 |
2009年 | 11篇 |
2008年 | 7篇 |
2007年 | 3篇 |
2006年 | 3篇 |
2005年 | 8篇 |
2004年 | 1篇 |
2003年 | 5篇 |
2002年 | 4篇 |
2001年 | 3篇 |
1999年 | 1篇 |
1996年 | 2篇 |
1993年 | 1篇 |
1989年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1980年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有132条查询结果,搜索用时 281 毫秒
71.
Anoop Nayak 《Geoforum》2003,34(3):303-315
This article seeks to bring young respondents more sharply into focus by considering fear of crime ‘through children’s eyes’. By incorporating children’s perspectives it is argued that more inclusive and integrative community safety initiatives may arise. Inspired by the recent flowering of research undertaken in childhood studies by social and cultural geographers, the study seeks to make a theoretical, empirical and spatial contribution to debates in the field. Based on the findings of a large-scale school survey, the responses indicate that children have an acute place-based sensitivity to a range of highly relevant community safety issues. This includes detailed reflections concerning the place of policing, boredom, youth gangs, motorcars and drugs in their neighbourhoods. It is suggested that the inclusion of children’s accounts into geographical debates not only enriches our knowledge of childhood studies, but also adds detail and texture to our understandings of fear of crime. 相似文献
72.
Geotechnical and Geological Engineering - Lithomargic clay is found along the Eastern and Western coasts of Southern India. Presence of weak soils like lithomargic clay below the foundations, cause... 相似文献
73.
M. Krishnapriya A. Bhuvana Chandra Rabindra K. Nayak N. R. Patel P. V. N. Rao V. K. Dadhwal 《Journal of the Indian Society of Remote Sensing》2018,46(2):309-320
A study on seasonal and inter-annual variability of the atmospheric CO2 is carried out based on National Oceanic and Atmospheric Administration Carbon Tracker (NOAACT) re-analysis and satellite measurements of mid-troposphere CO2 by Atmosphere Infrared Sounder on board NASA’s Aqua and lower troposphere CO2 by Greenhouse-gas Observing Satellite. Seasonal and non-seasonal components of each time series were extracted by means of least square based harmonic analysis procedure. The data of surface CO2 fluxes used in the NOAACT are also analyzed to examine its relationship with the atmosphere CO2 variability at different time scales. There exists good consistency between NOAACT analysis and satellite observations in their respective seasonal harmonics and climatology. Surface layer CO2 exhibits large climatological mean over the regions of major anthropogenic sources together with strong seasonal cycle over the humid and cold climatic terrestrial regions especially over the northern hemisphere. Existence of high coherency with the different components of the surface fluxes shows that surface layer atmosphere CO2 seasonality is primarily contributed from the terrestrial ecosystem exchanges and secondarily by anthropogenic and oceanic exchanges. The mid-troposphere CO2 exhibits large values associated with climatology and amplitudes of semi-annual and annual cycles over the northern extra tropics and Polar Regions along with a gradual decreasing trend from northern to southern hemisphere. Inter-annual variability of atmospheric CO2 in the NOAACT in some extent is consistent with the satellite observations. Large scale circulation patterns, its fluctuations associated with ENSO events and large scale ecosystem disturbances have significant influence on the inter-annual variability. 相似文献
74.
75.
Mahala Biranchi Kumar Nayak Birendra Kumar Mohanty Pratap Kumar 《Natural Hazards》2015,75(2):1105-1125
Natural Hazards - The impacts of El Niño-Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) on tropical cyclone (TC) activity (intensity, frequency, genesis location, track and average... 相似文献
76.
Use of remote sensing,GIS and C++ for soil erosion assessment in the Shakkar River basin,India 总被引:1,自引:1,他引:0
Rupesh Jayaram Patil Shailesh Kumar Sharma Sanjay Tignath Aribam Priya Mahanta Sharma 《水文科学杂志》2017,62(2):217-231
Soil is an essential resource for human livelihoods. Soil erosion is now a global environmental crisis that threatens the natural environment and agriculture. This study aimed to assess the annual rate of soil erosion using distributed information for topography, land use and soil, with a remote sensing (RS) and geographical information system (GIS) approach and comparison of simulated with observed sediment loss. The Shakkar River basin, situated in the Narsinghpur and Chhindwara districts of Madhya Pradesh, India, was selected for this study. The universal soil loss equation (USLE) with RS and GIS was used to predict the spatial distribution of soil erosion occurring in the study area on a grid-cell basis. Thematic maps of rainfall erosivity factor (R), soil erodibility factor (K), topographic factor (LS), crop/cover management factor (C), and conservation/support practice factor (P) were prepared using annual rainfall data, soil map, digital elevation model (DEM) and an executable C++ program, and a satellite image of the study area in the GIS environment. The annual rate of soil erosion was estimated for a 15-year period (1992–2006) and was found to vary between 6.45 and 13.74 t ha?1 year?1, with an average annual rate of 9.84 t ha?1 year?1. The percentage deviation between simulated and observed values varies between 2.68% and 18.73%, with a coefficient of determination (R2) of 0.874. 相似文献
77.
78.
The regional climate model (RegCM4) is customized for 10-year climate simulation over Indian region through sensitivity studies on cumulus convection and land surface parameterization schemes. The model is configured over 30° E–120° E and 15° S–45° N at 30-km horizontal resolution with 23 vertical levels. Six 10-year (1991–2000) simulations are conducted with the combinations of two land surface schemes (BATS, CLM3.5) and three cumulus convection schemes (Kuo, Grell, MIT). The simulated annual and seasonal climatology of surface temperature and precipitation are compared with CRU observations. The interannual variability of these two parameters is also analyzed. The results indicate that the model simulated climatology is sensitive to the convection as well as land surface parameterization. The analysis of surface temperature (precipitation) climatology indicates that the model with CLM produces warmer (dryer) climatology, particularly over India. The warmer (dryer) climatology is due to the higher sensible heat flux (lower evapotranspiration) in CLM. The model with MIT convection scheme simulated wetter and warmer climatology (higher precipitation and temperature) with smaller Bowen ratio over southern India compared to that with the Grell and Kuo schemes. This indicates that a land surface scheme produces warmer but drier climatology with sensible heating contributing to warming where as a convection scheme warmer but wetter climatology with latent heat contributing to warming. The climatology of surface temperature over India is better simulated by the model with BATS land surface model in combination with MIT convection scheme while the precipitation climatology is better simulated with BATS land surface model in combination with Grell convection scheme. Overall, the modeling system with the combination of Grell convection and BATS land surface scheme provides better climate simulation over the Indian region. 相似文献
79.
S. P. Volvoikar G. N. Nayak 《International Journal of Environmental Science and Technology》2013,10(5):941-954
A large amount of material in the form of industrial effluents and urban sewage containing metal contaminants directly enters Dudh creek. Metals on entering the creek tend to settle at the bottom and become part of the sediments. The distribution of metals with depth reflects changes in their supply as well as diagenetic modifications with time. In the present study, an attempt has been made to understand the impact of waste discharged from Tarapur Maharashtra Industrial Development Corporation on Dudh creek. Two cores were collected, one close to the creek mouth and the other in the inner part of the creek. Sediment component, organic carbon and metal (vanadium, copper, nickel, lead, zinc, manganese, iron and aluminium) analyses were carried out on the two cores. The variation in the distribution of sediment components with depth reflects changes in hydrodynamic condition of the creek over the years. Increase in concentration of most of the metals in the upper part of the cores indicates additional input in recent years. The core collected in the inner part of the creek showed higher metal and organic carbon concentration as compared to the downstream core. This was very well supported by distribution of points on an isocon plot. Enrichment factor and index of geoaccumulation were used to find the extent of pollution in sediments of the creek. Correlation and R-mode factor analysis have also been computed to understand the association and source of metal input in sediments of Dudh creek. 相似文献
80.
R.?Shivashankar M.?R.?Dheerendra BabuEmail author Sitaram?Nayak V.?Rajathkumar 《Geotechnical and Geological Engineering》2011,29(5):749-757
Stone columns are found to be effective and economical ground improvement technique in soft grounds. Understanding its behaviour
when they are installed in stratified soils, in particular when the upper layer consists of weak soil, will be of great practical
significance. This paper presents results from a series of laboratory plate load tests carried out in unit cell tanks to investigate
the behaviour of stone columns in layered soils, consisting of weak soft clay overlying a relatively stronger silty soil,
for various thicknesses of the top layer. Tests were carried out with two types of loading (1) the entire area in the unit
cell tank loaded, to estimate the stiffness of improved ground and (2) only the stone column loaded, to estimate the limiting
axial capacity. Laboratory tests were carried out on a column of 90 mm diameter surrounded by layered soil, for an area ratio
of 15%. It is found that the depth of top weak layer thickness has a significant influence on the stiffness, load bearing
capacity and bulging behavior of stone columns. 相似文献