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151.
本文介绍了一种新的星载合成孔径雷达干涉测量数据处理技术(GeoWatch InSAR技术),具有下述特点和优势:1.对城市和郊区农村全面连续覆盖,不仅包括建筑物,而且包括路面、广场、飞机跑道等其他地物和半植被覆盖的自然地区;2.合成处理多景/多波段/多模式/多极化/多轨道/多卫星平台的数据,从而缩短观测时间,提高精度和覆盖;3.所有结果为真正射投影图像,支持各种比例尺和范围的面状连续监测;4.支持ERS-1&2、ENVISAT、ALOS PALSAR、JERS-1、RADARSAT-1&2、TerraSAR、COSMO-SkyMed(CSK)和将来中国的HJ1小雷达卫星群。用此技术处理了天津地区的ENVISAT数据,得到了范围(抽样间隔)分别为100km×100km(50m×50m)、天津市(20m×20m)、廊坊市(15m×15m)及胜芳镇(7m×7m)的全面连续的地面沉降率图像,显示了它在地面沉降监测中的独特优势和应用前景。 相似文献
152.
153.
Ch. Haniff 《Astrophysics and Space Science》2003,286(1-2):163-170
The opportunity to deliver high-angular resolution model-independent images is one of the most attractive prospects for optical/infrared
interferometry. In this paper I use simple imaging simulations to identify some of the practical difficulties that may arise
in achieving this goal with the VLTI. For the types of studies investigated here – stellar surface imaging and the mapping
of emission line disks – it is likely that the key challenges will be to measure the visibility function on a sufficiently
large range of baselines, and to secure accurate and reliable phase information.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
154.
Philippe Stee 《Astrophysics and Space Science》2003,286(1-2):225-236
Interferometry in the visible provides milliarcsecond spatial resolution and thus has been used for studying the circumstellar
environment of active hot stars. In this paper I will illustrate how the visibility modulus and phase can be used to better
constrain the physics of Be disks through results from the VLA, the MkII and the GI2T interferometers. I will insist on the
importance and the potential of coupling high angular resolution with high spectral resolution to the study of Be shells.
Finally I will present a possible study of the circumstellar disk of Be stars using the VLTI.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
155.
Software development costs for the Square Kilometre Array are likely to be very large – in the range of 1000–2000 person-year a total. This level of software effort is unprecedented in radio astronomy. Consequently the risk associated with software development is very large. This is common to many large science projects and so we can learn from such projects how to best mitigate against the risk. We present a shopping list of suggestions drawn from the experience in other projects. 相似文献
156.
A. Quirrenbach 《Astrophysics and Space Science》2003,286(1-2):277-289
The scientific capabilities of the VLT Interferometer can be substantially enhanced through new focal-plane instruments. Many
interferometric techniques– astrometry, phase-referenced imaging, nulling, and differential phase measurements – require control
of the phase to ≲ 1 rad; this capability will be provided at the VLTI by the PRIMA facility. Phase-coherent operation of the
VLTI will also make it possible to perform interferometry with spectral resolution up to R ∼ 100,000 by building fiber links
to the high-resolution spectrographs UVES and CRIRES. These developments will open new approaches to fundamental problems
in fields as diverse as extra solar planets,stellar atmospheres, circumstellar matter, and active galactic nuclei.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
157.
W. C. Danchi M. Bester L. J. Greenhill C. G. Degiacomi N. Geis D. Hale B. Lopez C. H. Townes 《Astrophysics and Space Science》1995,224(1-2):447-448
Visibility data and analyses are discussed for 16 late-type stars observed with the Infrared Spatial Interferometer (ISI) of the University of California, Berkeley. 相似文献
158.
Infrared speckle-masking observations of eleven binary systems with the 6-m Special Astrophysical Observatory telescope are presented. A resolution of 43 mas in J (1.25 µm) and 76 mas in K (2.2 µm) has been achieved in reconstructed images. Accurate magnitude differences, separations, and position angles have been determined for all the resolved binaries. The pair HR 1071 with an abnormally low lithium abundance is considered in more detail. 相似文献
159.
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
160.