全文获取类型
| 收费全文 | 106篇 |
| 免费 | 9篇 |
| 国内免费 | 5篇 |
专业分类
| 测绘学 | 37篇 |
| 地球物理 | 24篇 |
| 地质学 | 13篇 |
| 海洋学 | 1篇 |
| 天文学 | 32篇 |
| 综合类 | 6篇 |
| 自然地理 | 7篇 |
出版年
| 2024年 | 1篇 |
| 2021年 | 5篇 |
| 2020年 | 3篇 |
| 2019年 | 6篇 |
| 2018年 | 3篇 |
| 2017年 | 1篇 |
| 2016年 | 2篇 |
| 2015年 | 4篇 |
| 2014年 | 3篇 |
| 2013年 | 5篇 |
| 2011年 | 9篇 |
| 2010年 | 2篇 |
| 2009年 | 2篇 |
| 2008年 | 11篇 |
| 2007年 | 11篇 |
| 2006年 | 9篇 |
| 2005年 | 5篇 |
| 2004年 | 4篇 |
| 2003年 | 4篇 |
| 2002年 | 3篇 |
| 2001年 | 3篇 |
| 2000年 | 3篇 |
| 1999年 | 2篇 |
| 1998年 | 5篇 |
| 1995年 | 3篇 |
| 1994年 | 6篇 |
| 1992年 | 4篇 |
| 1991年 | 1篇 |
排序方式： 共有120条查询结果，搜索用时 390 毫秒
41.
. The excess radio-path delay due to the atmospheric water vapor, the wet delay, can be derived from water vapor radiometer
(WVR) measurements. WVR data used for external calibration of space geodetic measurements are not always acquired in the directions
of the space geodetic signal sources, thus extrapolation and interpolation methods for the wet delay are needed. We evaluate
three different methods using approximately 10 days of WVR measurements. Two methods, the gradient method and turbulence method,
use the directional information in the data, while the third method used is linear regression in time regardless of the direction
of the observations. The turbulence method yielded at least 10% less RMS estimation error than the errors from the other two
methods.
Received: 20 May 1997 / Accepted: 15 December 1997 相似文献
42.
InSAR技术在矿区沉降监测中的应用研究 总被引：1，自引：1，他引：0
介绍了应用InSAR技术监测矿区地表沉降以及地下开采活动的原理;利用重轨差分InSAR技术获得了峰峰矿区地表ENVISAT和JERS 1的雷达形变干涉相位图;分析了在矿区地表沉降过程中ENVISATC波段和JERS 1 L波段形变干涉相位图的相干特性、相位特性以及干涉测量技术在矿区地表沉降监测中应用的可行性和局限性。实验结果表明,利用C波段和L波段雷达数据可以实施对矿区地表沉降的监测,但是C波段雷达受到空间干涉基线的限制更加严格,如果要实现对矿区地表沉降的监测,需要充分利用每个卫星回访时期的雷达数据,建立长时序的星载雷达形变干涉相位图序列,才能较好地实现矿区地表沉降监测。 相似文献
43.
44.
高分辨统计重建中,随机误差影响着统计结果的信噪比,从而限制了探测目标时所能达到的精度。通过推导给出了单星斑点干涉术统计结果信噪比的数学表达式,并模拟计算了不同视宁度参量r0和不同光子数下斑点图统计功率谱环带上的信噪比,模拟计算结果和理论数学模型吻合较好,最后对一些实测数据进行了处理和分析。 相似文献
45.
We present an interferometric technique for the reconstruction of ultra-wide band impulsive signals from point sources. This highly sensitive method was developed for the search for ultra-high energy neutrinos with the ANITA experiment but is fully generalizable to any antenna array detecting radio impulsive events. Applications of the interferometric method include event reconstruction, thermal noise and anthropogenic background rejection, and solar imaging for calibrations. We illustrate this technique with applications from the analysis of the ANITA-I and ANITA-II data in the 200–1200 MHz band. 相似文献
46.
Batuhan Osmanoğlu Timothy H. Dixon Shimon Wdowinski Enrique Cabral-Cano Yan Jiang 《International Journal of Applied Earth Observation and Geoinformation》2011
We analyzed 23 satellite SAR (synthetic aperture radar) scenes using Persistent Scatter Interferometry (PSI) to study subsidence in Mexico City associated with groundwater withdrawal. The data were acquired by the Envisat ASAR system between January 2004 and July 2006. The spatial pattern of subsidence and the maximum subsidence rate (300 mm/year) are similar to earlier studies. Comparison to independent GPS data indicates RMS agreement between the two techniques of 6.9 mm/year, about the level expected based on joint data uncertainty. Significant annual variation in the GPS vertical data is not observed, suggesting minimal aquifer recharge during the rainy season, and justifying a simple linear model of phase variation through time for the PSI analysis. 相似文献
47.
The Indian subcontinent is one of the most earthquake-prone regions of the world. The Himalayas are well known for high seismic activity, and the ongoing northwards drift of the Indian plate makes the Himalaya geodynamically active. During the last three decades, several major earthquakes occurred at the plate interiors and boundaries in this subcontinent causing massive losses. Therefore, one of the major challenges in seismology has been to estimate long recurrence period of large earthquakes where most of the classical Probabilistic Seismic Hazard Approaches fail due to short catalogues used in the prediction models. Therefore, during the past few decades, the Himalayan region has been studied extensively in terms of the present ongoing displacements. In this context the present study has been carried out to estimate the surface displacement in a seismically active region of the Himalaya, in between Ganga and Yamuna Tear, using multi-temporal Synthetic Aperture Radar (SAR) Interferometry. A displacement rate of 6.2–8.2 mm/yr in N14°E direction of the Indian plate towards the Tibetan plate has been obtained. It has been noted that the estimated convergence rate using Differential SAR Interferometry technique is relatively low in comparison with those obtained from previous classical studies. The reported low convergence rate may be due to the occurrence of silent/quite earthquakes, aseismic slip, differential movement of Delhi Hardwar ridge, etc. Therefore, in view of the contemporary seismicity and conspicuous displacements, a study of long-term observations of this surface movement has been recommended in future through a time-series SAR Interferometry analysis. 相似文献
48.
We present a novel methodology for integration of multiple InSAR data sets for computation of two dimensional time series of ground deformation. The proposed approach allows combination of SAR data acquired with different acquisition parameters, temporal and spatial sampling and resolution, wavelength and polarization. Produced time series have combined coverage, improved temporal resolution and lower noise level. We apply this methodology for mapping coal mining related ground subsidence and uplift in the Greater Region of Luxembourg along the French–German border. For this we processed 167 Synthetic Aperture Radar ERS-1/2 and ENVISAT images acquired between 1995 and 2009 from one ascending (track 29) and one descending (track 337) tracks and created over five hundred interferograms that were used for time series analysis. Derived vertical and east–west linear deformation rates show with remarkable precision a region of localized ground deformation located above and caused by mining and post-mining activities. Time series of ground deformation display temporal variability: reversal from subsidence to uplift and acceleration of subsidence in the vertical component, and horizontal motion toward the center of the subsidence on the east–west component. InSAR results are validated by leveling measurements collected by the French Geological Survey (BRGM) during 2006–2008. We determined that deformation rate changes are mainly caused by water level variations in the mines. Due to higher temporal and spatial resolution the proposed space-borne method detected a larger number of subsidence and uplift areas in comparison to leveling measurements restricted to annual monitoring of benchmark points along roads. We also identified one deformation region that is not precisely located above the mining sites. Comparison of InSAR measurements with the water levels measured in the mining pits suggest that part of the water that filled the galleries after termination of the dewatering systems may come from this region. Providing that enough SAR data is available, this method opens new opportunities for detecting and locating man-made and natural ground deformation signals with high temporal resolution and precision. 相似文献
49.
This chapter gives some indications on the selection of suitable astronomical calibrators for interferometric observations. After an introduction to interferometric calibrations, we will focus on the criteria, steps and tools developed by ESO to prepare VLTI observations and to select calibrators. Although the tools described here are focused on VLTI, the problem of astronomical calibrators is the same for the other interferometers and can be approached in the same way. 相似文献
50.