排序方式: 共有122条查询结果,搜索用时 28 毫秒
21.
Slope inclinometers for landslides 总被引:1,自引:1,他引:1
Slope inclinometers/indicators are used to determine the magnitude, rate, direction, depth, and type of landslide movement.
This information is usually vitally important for understanding the cause, behavior, and remediation of a landslide. However,
many inclinometer measurements fail to achieve these intended aims because of lack of appreciation of the many factors that
need to be correctly implemented during installation, monitoring, and data reduction to yield useful data. This paper presents
some guidelines for understanding, installing, and interpreting slope inclinometers and presents three case histories that
illustrate some of the pitfalls that can develop if these guidelines are not followed. 相似文献
22.
电磁波信号在地球大气中的传播受到折射的影响,传播的方向发生了改变,传播的路径变为曲线,长度大于直线距离,相应的传播时间也被延长了,采用一个简化的球对称大气模型计算了光线在不同天顶距下由于路径弯曲而引起的延迟改正. 相似文献
23.
We describe the four software modules that have lead to highly automated observing with CGS4 on UKIRT. 相似文献
24.
论述了太阳二维光谱观测和研究的重大意义,综述了二维光谱观测技术和仪器的进展,特别介绍了应用CCD的成像光谱仪的最近发展。文中还介绍了近年来二维光谱观测研究所取得的一些新结果,展望了未来观测技术和课题研究的发展前景。 相似文献
25.
W. Alan Delamere Livio L. Tornabene Kris Becker Nathan T. Bridges Dennis Gallagher Laszlo Keszthelyi Guy K. McArthur Moses Milazzo Nicolas Thomas 《Icarus》2010,205(1):38-52
HiRISE has been producing a large number of scientifically useful color products of Mars and other planetary objects. The three broad spectral bands, coupled with the highly sensitive 14 bit detectors and time delay integration, enable detection of subtle color differences. The very high spatial resolution of HiRISE can augment the mineralogic interpretations based on multispectral (THEMIS) and hyperspectral datasets (TES, OMEGA and CRISM) and thereby enable detailed geologic and stratigraphic interpretations at meter scales. In addition to providing some examples of color images and their interpretation, we describe the processing techniques used to produce them and note some of the minor artifacts in the output. We also provide an example of how HiRISE color products can be effectively used to expand mineral and lithologic mapping provided by CRISM data products that are backed by other spectral datasets. The utility of high quality color data for understanding geologic processes on Mars has been one of the major successes of HiRISE. 相似文献
26.
Half of the energy ever emitted by stars and accreting objects comes to us in the far-infrared (FIR) waveband and has yet
to be properly explored. We propose a powerful Far-InfraRed Interferometer mission, FIRI, to carry out high-resolution imaging spectroscopy in the FIR. This key observational capability is essential to reveal how
gas and dust evolve into stars and planets, how the first luminous objects in the Universe ignited, how galaxies formed, and
when super-massive black holes grew. FIRI will disentangle the cosmic histories of star formation and accretion onto black holes and will trace the assembly and evolution
of quiescent galaxies like our Milky Way. Perhaps most importantly, FIRI will observe all stages of planetary system formation and recognise the birth of planets via its ability to image the dust
structures in planetary systems. FIRI is an observatory-class mission concept: three cold, 3.5-m apertures, orbiting a beam-combining module, with separations
of up to 1 km, free-flying or tethered, operating between 25 and 385 μm, using the interferometric direct-detection technique
to ensure μJy sensitivity and 0.02” resolution at 100 μm, across an arcmin2 instantaneous field of view, with a spectral resolution, R ~ 5,000 and a heterodyne system with R ~ 1 million. Although FIRI is an ambitious mission, we note that FIR interferometry is appreciably less demanding than at shorter wavelengths.
On behalf of the following scientists: Javier Alcolea, David Alexander, Philippe Andre, Rafael Bachiller, Mike Barlow, Andrey
Baryshev, Alain Baudry, Carlton Baugh, Dominic Benford, Ted Bergin, Frank Bertoldi, Geoffrey Blake, Andrew Blain, Sylvain
Bontemps, Franois Bouchet, Francois Boulanger, Jeroen Bouwman, Jonathan Braine, Bernhard Brandl, Valentin Bujarrabal, Sylvie
Cabrit, Martin Caldwell, Daniela Calzetti, John Carpenter, Emmanuel Caux, Cecilia Ceccarelli, Jose Cernicharo Quintanilla,
Pierre Chanial, Andrea Cimatti, John Conway, Pierre Cox, Dave Clements, Bill Dent, Gianfranco De Zotti, Carsten Dominik, Loretta
Dunne, Steve Eales, Nicholas Elias, Duncan Farrah, Mike Fich, Jacqueline Fischer, Alberto Franceschini, David Frayer, Carlos
Frenk, Gary Fuller, Maryvonne Gerin, Martin Giard, Thijs de Graauw, Gian Luigi Granato, Jane Greaves, Matt Griffin, Rolf Guesten,
Stephane Guilloteau, Martin Harwit, Thomas Henning, Eric Herbst, Michiel Hogerheijde, Kate Isaak, Christine Joblin, Eelco
van Kampen, Hubert Klahr, Kirsten Kraiberg Knudsen, Oliver Krause, Cedric Lacey, Robert Laing, Jean-Michel Lamarre, Huib Jan
van Langevelde, David Leisawitz, Simon Lilly, Darek Lis, Rene Liseau, Enrico Lorenzini, Dieter Lutz, Michael Macintyre, Suzanne
Madden, Roberto Maiolino, Jesus Martin-Pintado, Karine Mercier, Karl Menton, Vincent Minier, Raphael Moreno, Harvey Moseley,
Takao Nakagawa, David Neufeld, Michael Olberg, Seb Oliver, Luca Olmi, Goran Olofsson, Hans Olofsson, Mat Page, Pantelis Papadopoulos,
Juan Pardo, John Pearson, Ismael Perez-Fournon, Sabine Philipp, Rene Plume, Albrecht Poglitsch, Jean-Loup Puget, John Richer,
Dimitra Rigopoulou, Stephen Rinehart, Peter Roelfsema, Paolo Saraceno, Rudolf Schieder, Karl-Friedrich Schuster, Gene Serabyn,
Stephen Serjeant, Robert Simon, Ian Smail, Luigi Spinoglio, Jason Stevens, Eckhard Sturm, Juergen Stutzki, Bruce Swinyard,
Emma Taylor, Floris van der Tak, Leonardo Testi, Wing-Fai Thi, Mattia Vaccari, Lars Venema, Laurent Vigroux, Serena Viti,
Catherine Vlahakis, Christoffel Waelkens, Malcolm Walmsley, Fabian Walter, Rens Waters, Paul van der Werf, Paul Wesselius,
Glenn White, Wolfgang Wild, Tom Wilson, Adam Woodcraft, Gillian Wright, FriedrichWyrowski, Harold Yorke, Min Yun, Jonas Zmuidzinas 相似文献
27.
J. E. J. Lovell H. Hirabayashi H. Kobayashi Y. Murata P. G. Edwards G. A. Moellenbrock S. Horiuchi E. B. Fomalont S. Kameno K. M. Shibata 《New Astronomy Reviews》1999,43(8-10)
An overview and status report of the VLBI Space Observatory Programme is presented. 相似文献
28.
The utilisation of sound backscattered from sediments in suspension, to measure profiles of near-bed particle size and concentration, has been gaining increasing acceptance and usage by sedimentologists and coastal engineers over the past two decades. To obtain the sediment parameters from the backscattered signal requires an inversion to be conducted on the signal and this necessitates a system calibration. The calibration can be carried out by detailed acoustic and electronic measurements, or alternatively by measuring the backscattering from suspensions with known scattering characteristics. Here, we explore the latter approach and describe in some detail the calibration of a triple frequency acoustic backscatter system. The aim is to provide coastal scientists involved in using acoustics as a tool for sediment transport research, with a clear exposition of the calibration process. Suspensions of glass spheres of varying particle size were used as the calibration scatterers. To interpret the signal backscatter from the suspension of glass spheres a simple model for sphere scattering is presented. The results show that consistent calibration results can be obtained in a relatively simple and robust manner. 相似文献
29.
We investigate, by ray-trace simulation, two hard X-ray telescopes based on microchannel plate (MCP) optics. The first is the, by now well known, lobster-eye geometry, while the second is a novel design. The second design uses a pair of MCPs with square channels packed in a radial fashion and represents a conical approximation to the Wolter type I configuration. We show that such telescopes can provide X-ray imaging at energies up to 100 keV. Effective area may be scaled arbitrarily by co-aligning many MCP optics. As an example, we calculate that 50 parallel Wolter I units each of 60 mm diameter and 5 m focal length yield a sensitivity of 1 milli Crab at 45 keV in a 105 second integration. 相似文献
30.
Chris Benn 《New Astronomy Reviews》2006,49(10-12):625
NAOMI is the AO system of the 4.2-m William Herschel Telescope on La Palma. It delivers an AO-corrected image to a lenslet array at the focal plane of the optical integral-field spectrograph OASIS. The resulting 1100 spectra are imaged onto a high-QE, low-fringing MITLL3 CCD. A range of spectroscopic and spatial (0.09–0.42 arcsec/lenslet) configurations is available. At wavelength 0.7 μm, the NAOMI-corrected FWHM is typically half that of the natural seeing. Scheduled OASIS observing began in semester 2004B, with 9 programmes awarded a total of 26 nights during the first year of operation. A Rayleigh laser guide star is under development, with first light expected summer 2006. In conjunction with NAOMI/OASIS, this will provide a unique facility: AO-corrected optical integral-field spectroscopy anywhere on the northern sky. 相似文献