全文获取类型
收费全文 | 58篇 |
免费 | 2篇 |
专业分类
测绘学 | 9篇 |
大气科学 | 15篇 |
地球物理 | 4篇 |
地质学 | 14篇 |
海洋学 | 4篇 |
天文学 | 12篇 |
自然地理 | 2篇 |
出版年
2022年 | 1篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 4篇 |
2015年 | 1篇 |
2014年 | 1篇 |
2013年 | 4篇 |
2012年 | 3篇 |
2011年 | 1篇 |
2010年 | 1篇 |
2008年 | 6篇 |
2007年 | 1篇 |
2006年 | 5篇 |
2005年 | 3篇 |
2004年 | 4篇 |
2003年 | 3篇 |
2002年 | 1篇 |
2001年 | 1篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1988年 | 1篇 |
1984年 | 2篇 |
排序方式: 共有60条查询结果,搜索用时 15 毫秒
21.
D. Bala Subrahamanyam S. Indira Rani Radhika Ramachandran P. K. Kunhikrishnan 《Ocean Science Journal》2008,43(4):165-173
In this article, we describe a simple yet effective method for insertion of observational datasets in a mesoscale atmospheric
model used in one-dimensional configuration through Nudging. To demonstrate the effectiveness of this technique, vertical
profiles of meteorological parameters obtained from GLASS Sonde launches from a tiny island of Kaashidhoo in the Republic
of Maldives are injected in a mesoscale atmospheric model — Advanced Regional Prediction System (ARPS), and model simulated
parameters are compared with the available observational datasets. Analysis of one-time nudging in the model simulations over
Kaashidhoo show that incorporation of this technique reasonably improves the model simulations within a time domain of +6
to +12 Hrs, while its impact on +18 Hrs simulations and beyond becomes literally null. 相似文献
22.
We perform large-eddy simulation (LES) of a moderately convective atmospheric boundary layer (ABL) using a prognostic subfilter-scale
(SFS) model obtained by truncating the full conservation equations for the SFS stresses and fluxes. The truncated conservation
equations contain production mechanisms that are absent in eddy-diffusivity closures and, thus, have the potential to better
parametrize the SFS stresses and fluxes. To study the performance of the conservation-equation-based SFS closure, we compare
LES results from the surface layer with observations from the Horizontal Array Turbulence Study (HATS) experiment. For comparison,
we also show LES results obtained using an eddy-diffusivity closure. Following past studies, we plot various statistics versus
the non-dimensional parameter, Λ
w
/Δ, where Λ
w
is the wavelength corresponding to the peak in the vertical velocity spectrum and Δ is the filter width. The LES runs are
designed using different domain sizes, filter widths and surface fluxes, in order to replicate partly the conditions in the
HATS experiment. Our results show that statistics from the different LES runs collapse reasonably and exhibit clear trends
when plotted against Λ
w
/Δ. The trends exhibited by the production terms in the modelled SFS conservation equations are qualitatively similar to those
seen in the HATS data with the exception of SFS buoyant production, which is underpredicted. The dominant production terms
in the modelled SFS stress and flux budgets obtained from LES are found to approach asymptotically constant values at low
Λ
w
/Δ. For the SFS stress budgets, we show that several of these asymptotes are in good agreement with their corresponding theoretical
values in the limit Λ
w
/Δ → 0. The modelled SFS conservation equations yield trends in the mean values and fluctuations of the SFS stresses and fluxes
that agree better with the HATS data than do those obtained using an eddy-diffusivity closure. They, however, underpredict
considerably the level of SFS anisotropy near the wall when compared to observations, which could be a consequence of the
shortcomings in the model used for the pressure destruction terms. Finally, we address the computational cost incurred due
to the use of additional prognostic equations. 相似文献
23.
It is shown how the computational burden of source localization by matched field processing (MFP) can be significantly reduced (20 to 30 times) by expressing the correlation in terms of a discrete Fourier transform and using the fast Fourier transform (FFT) algorithm. The price paid to achieve increased speed is in the form of quantization phase errors. It is shown through analysis and computer simulation that the quantization errors reduce the source peak height, depending upon the size of DFT. The proposed fast MFP works for range localization only. However, the depth estimation is possible by repeated application of the above algorithm for different depths 相似文献
24.
25.
Ahamed Ibrahim S.N. Sri Shalini S Ramachandran A Palanivelu K 《Journal of Atmospheric Chemistry》2022,79(1):39-66
Journal of Atmospheric Chemistry - At the pandemic of COVID-19, the movement of business and other non-essential activities were majorly restricted at the end of March 2020 in India and continued... 相似文献
26.
This experimental research deals with using steel scrap as a heterogeneous catalyst. This catalyzes the oxidation reaction of real textile dye wastewater based on a modified solar photo‐Fenton oxidation process. Morphologic analysis and mapping of the elementary composition of the steel scrap have been carried out by scanning electron microscopy. The effects of concentration of H2O2, the pH of the solution and the catalyst loading on the degradation of textile dye wastewater are elucidated. Kinetic studies have been performed for the decolorization of wastewater under optimum conditions. It could be concluded that the steel scrap is a potential substitute for ferrous salts as a catalyst for the solar photo‐Fenton reaction. 相似文献
27.
28.
Prasanta Kumar Bal Andimuthu Ramachandran Kandasamy Palanivelu Perumal Thirumurugan Rajadurai Geetha Bhaski Bhaskaran 《Asia-Pacific Journal of Atmospheric Sciences》2016,52(4):353-369
This study presents a comprehensive assessment of the possible regional climate change over India by using Providing REgional Climates for Impacts Studies (PRECIS), a regional climate model (RCM) developed by Met Office Hadley Centre in the United Kingdom. The lateral boundary data for the simulations were taken from a sub-set of six members sampled from the Hadley Centre’s 17- member Quantified Uncertainty in Model Projections (QUMP) perturbed physics ensemble. The model was run with 25 km × 25 km resolution from the global climate model (GCM) - HadCM3Q at the emission rate of special report on emission scenarios (SRES) A1B scenarios. Based on the model performance, six member ensembles running over a period of 1970-2100 in each experiment were utilized to predict possible range of variations in the future projections for the periods 2020s (2005-2035), 2050s (2035-2065) and 2080s (2065-2095) with respect to the baseline period (1975-2005). The analyses concentrated on maximum temperature, minimum temperature and rainfall over the region. For the whole India, the projections of maximum temperature from all the six models showed an increase within the range 2.5°C to 4.4°C by end of the century with respect to the present day climate simulations. The annual rainfall projections from all the six models indicated a general increase in rainfall being within the range 15-24%. Mann-Kendall trend test was run on time series data of temperatures and rainfall for the whole India and the results from some of the ensemble members indicated significant increasing trends. Such high resolution climate change information may be useful for the researchers to study the future impacts of climate change in terms of extreme events like floods and droughts and formulate various adaptation strategies for the society to cope with future climate change. 相似文献
29.
30.
A. A. Deshpande & R. Ramachandran 《Monthly notices of the Royal Astronomical Society》1998,300(2):577-582
In this paper we propose a scenario for the formation of a population of baryon-rich, dark-matter-deficient dwarf galaxies at high redshift from the mass swept out in the intergalactic medium (IGM) by energetic outflows from luminous quasars. We predict the intrinsic properties of these galaxies, and examine the prospects for their observational detection in the optical, X-ray and radio wavebands. Detectable thermal Sunyaev–Zel'dovich decrements on arcminute scales in the cosmic microwave background radiation maps are expected during the shock-heated expanding phase from these hot bubbles. We conclude that the optimal detection strategy for these dwarfs is via narrow-band Lyman-α imaging of regions around high-redshift quasars. A scaled-down (in the energetics) version of the same model is speculated upon as a possible mechanism for forming pre-galactic globular clusters. 相似文献