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81.
T. A. Shatilina G. Sh. Tsitsiashvili T. V. Radchenkova 《Russian Meteorology and Hydrology》2010,35(11):740-743
Peculiarities are investigated of the air temperature variation tendencies at some stations of the Far East in 1976–2005.
The estimate of linear trend equation coefficients is computed according to the air temperature observation data using the
least squares method. It is demonstrated that the air temperature trend in northern regions possesses a small probability
at small values of residual variability. In the southern regions, the trend significance increases for almost all seasons
at small values of residual variability. At midlatitude stations, the trend significance in January and February decreases
considerably due to the large values of residual variability. 相似文献
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Daniel G. Brown Rick Riolo Derek T. Robinson Michael North William Rand 《Journal of Geographical Systems》2005,7(1):25-47
The use of object-orientation for both spatial data and spatial process models facilitates their integration, which can allow exploration and explanation of spatial-temporal phenomena. In order to better understand how tight coupling might proceed and to evaluate the possible functional and efficiency gains from such a tight coupling, we identify four key relationships affecting how geographic data (fields and objects) and agent-based process models can interact: identity, causal, temporal and topological. We discuss approaches to implementing tight integration, focusing on a middleware approach that links existing GIS and ABM development platforms, and illustrate the need and approaches with example agent-based models. 相似文献
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T.W. Foresman T. Cary T. Shupin R. Eastman J.E. Estes N. Faust J.R. Jensen K.K. Kemp 《ISPRS Journal of Photogrammetry and Remote Sensing》1997,52(6):294-300
The Remote Sensing Core Curriculum (RSCC) was initiated in 1993 to meet the demands for a college-level set of resources to enhance the quality of education across national and international campuses. The American Society of Photogrammetry and Remote Sensing adopted the RSCC in 1996 to sustain support of this educational initiative for its membership and collegiate community. A series of volumes, containing lectures, exercises, and data, is being created by expert contributors to address the different technical fields of remote sensing. The RSCC program is designed to operate on the Internet taking full advantage of the World Wide Web (WWW) technology for distance learning. The issues of curriculum development related to the educational setting, with demands on faculty, students, and facilities, is considered to understand the new paradigms for WW-influenced computer-aided learning. The WWW is shown to be especially appropriate for facilitating remote sensing education with requirements for addressing image data sets and multimedia learning tools. The RSCC is located at http://www.umbc.edu/rscc 相似文献
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In October 1998 the IGEX field campaign, the first coordinated international effort to monitor GLONASS satellites on global
basis, was started. Currently about 40 institutions worldwide support this effort either by providing GLONASS tracking data
or in operating related data and analysis centers. The increasing quality and consistency of the calculated GLONASS orbits
(about 25 cm early in 2000), even after the end of the official IGEX field campaign, are shown. Particular attention is drawn
to the combination of precise ephemerides in order to generate a robust, reliable and complete IGEX orbits product. Some problems
in modeling the effect of solar radiation pressure on GLONASS satellites are demonstrated. Finally, the expected benefits
and prospects of the upcoming International GLOnass Service-Pilot Project (IGLOS-PP) of the International GPS Service (IGS)
are discussed in more detail.
Received: 17 August 2000 / Accepted: 12 April 2001 相似文献
90.
Tongjiang Wang Nelson L. Reginald Joseph M. Davila O. Chris St. Cyr William T. Thompson 《Solar physics》2017,292(8):97
Three-dimensional electron density distributions in the solar corona are reconstructed for 100 Carrington rotations (CR 2054?–?2153) during 2007/03?–?2014/08 using the spherically symmetric method from polarized white-light observations with the inner coronagraph (COR1) onboard the twin Solar Terrestrial Relations Observatory (STEREO). These three-dimensional electron density distributions are validated by comparison with similar density models derived using other methods such as tomography and a magnetohydrodynamics (MHD) model as well as using data from the Solar and Heliospheric Observatory (SOHO)/Large Angle and Spectrometric Coronagraph (LASCO)-C2. Uncertainties in the estimated total mass of the global corona are analyzed based on differences between the density distributions for COR1-A and -B. Long-term variations of coronal activity in terms of the global and hemispheric average electron densities (equivalent to the total coronal mass) reveal a hemispheric asymmetry during the rising phase of Solar Cycle 24, with the northern hemisphere leading the southern hemisphere by a phase shift of 7?–?9 months. Using 14 CR (\(\approx13\)-month) running averages, the amplitudes of the variation in average electron density between Cycle 24 maximum and Cycle 23/24 minimum (called the modulation factors) are found to be in the range of 1.6?–?4.3. These modulation factors are latitudinally dependent, being largest in polar regions and smallest in the equatorial region. These modulation factors also show a hemispheric asymmetry: they are somewhat larger in the southern hemisphere. The wavelet analysis shows that the short-term quasi-periodic oscillations during the rising and maximum phases of Cycle 24 have a dominant period of 7?–?8 months. In addition, it is found that the radial distribution of the mean electron density for streamers at Cycle 24 maximum is only slightly larger (by \(\approx30\%\)) than at cycle minimum. 相似文献