On the geology of south-eastern Kincardineshire     

Robert Campbell 《Proceedings of the Geologists' Association. Geologists' Association》1912,23(5):295-298

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Geröllführende Schiefer und andere Trümmergesteine aus der Zentralzone der Ostalpen     

Schwinner  Robert 《International Journal of Earth Sciences》1929,20(3):211-244

Ohne Zusammenfassung  相似文献   

Value-added Impact of Geostationary Hyperspectral Infrared Sounders on Local Severe Storm Forecasts——via a Quick Regional OSSE     

Zhenglong LI  Jun LI  Pei WANG  Agnes LIM  Jinlong LI  Timothy J.SCHMIT  Robert ATLAS  Sid-Ahmed BOUKABARA  Ross N.HOFFMAN 《大气科学进展》2018,35(10):1217-1230

Accurate atmospheric temperature and moisture information with high temporal/spatial resolutions are two of the key parameters needed in regional numerical weather prediction(NWP) models to reliably predict high-impact weather events such as local severe storms(LSSs). High spectral resolution or hyperspectral infrared(HIR) sounders from geostationary orbit(GEO) provide an unprecedented source of near time-continuous, three-dimensional information on the dynamic and thermodynamic atmospheric fields—an important benefit for nowcasting and NWP-based forecasting. In order to demonstrate the value of GEO HIR sounder radiances on LSS forecasts, a quick regional OSSE(Observing System Simulation Experiment)framework has been developed, including high-resolution nature run generation, synthetic observation simulation and validation, and impact study on LSS forecasts. Results show that, on top of the existing LEO(low earth orbit) sounders, a GEO HIR sounder may provide value-added impact [a reduction of 3.56% in normalized root-mean-square difference(RMSD)] on LSS forecasts due to large spatial coverage and high temporal resolution, even though the data are assimilated every 6 h with a thinning of 60 km. Additionally, more frequent assimilations and smaller thinning distances allow more observations to be assimilated, and may further increase the positive impact from a GEO HIR sounder. On the other hand, with denser and more frequent observations assimilated, it becomes more difficult to handle the spatial error correlation in observations and gravity waves due to the limitations of current assimilation and forecast systems(such as a static background error covariance). The peak reduction of 4.6% in normalized RMSD is found when observations are assimilated every 3 h with a thinning distance of 30 km.  相似文献   

Optimal international technology cooperation for the low-carbon transformation     

Anselm Schultes  Marian Leimbach  Gunnar Luderer  Robert C. Pietzcker  Lavinia Baumstark  Nico Bauer 《Climate Policy》2018,18(9):1165-1176

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GIS diffusion in Uganda     

Sami Eria  Robert B. McMaster 《International journal of geographical information science》2017,31(5):884-906

Despite myriad studies having been carried out on the diffusion of geographical information systems (GIS) technology, only a limited number have been done within the context of developing countries. This paper addresses the research question, how did the diffusion of GIS technology occur in Uganda? Mixed methods were used for data collection, and analysis was performed using a theoretical framework called the diffusion of innovations (DOI). The results of the study showed that the adoption of GIS by institutions in Uganda occurred in a classic diffusion pattern consistent with diffusion theory. Adoption of GIS was promoted by its relative advantage over, and compatibility with, existing technologies. It was characterized by both heterophilous and homophilous communication channels, and influenced by change agents and champions. Its rate of adoption followed an S-shaped diffusion curve, and was hampered by bureaucracy, and patronage-based societal norms. This study makes a contribution to literature on GIS diffusion in developing countries.  相似文献   

Characteristics of stone covers on the surface of basalt flows in arid, northeast Jordan     

David L. Higgitt  Robert J. Allison 《Geomorphology》1999,28(3-4)

Variations in the stone covers on desert surfaces have implications for the operation of hydrological processes. Some recent attention has been given to the difficulties of identifying and quantifying relevant characteristics of stone covers. Investigation of how such characteristics vary in relation to geological and topographical controls are limited. Results are presented of a field study of the characteristics of stone covers on four lithologies in the late Tertiary to Quaternary basalt plateau of northeast Jordan. Marked variations occur in clast dimensions and the characteristics of sorting between lithologies which are likely to affect hydrological response. A more subtle control, relating to slope conditions, is superimposed on the lithological differences. R- and Q-mode factor analysis identifies groupings within the data, which demonstrate the distinctiveness of different lithologies. Characteristics of the stone covers on sites affected by human occupation are markedly different from undisturbed sites on the same lithology.  相似文献   

Analysis of Difference Between Direct and Geodetic Mass Balance Measurements at South Cascade Glacier, Washington   总被引：2，自引：0，他引：2  

Robert M. Krimmel 《Geografiska Annaler: Series A, Physical Geography》1999,81(4):653-658

Net mass balance has been measured since 1958 at South Cascade Glacier using the 'direct method,' e.g. area averages of snow gain and firn and ice loss at stakes. Analysis of cartographic vertical photography has allowed measurement of mass balance using the 'geodetic method' in 1970, 1975, 1977, 1979–80, and 1985–97. Water equivalent change as measured by these nearly independent methods should give similar results. During 1970–97, the direct method shows a cumulative balance of about −15 m, and the geodetic method shows a cumulative balance of about −22 m. The deviation between the two methods is fairly consistent, suggesting no gross errors in either, but rather a cumulative systematic error. It is suspected that the cumulative error is in the direct method because the geodetic method is based on a non-changing reference, the bedrock control, whereas the direct method is measured with reference to only the previous year's summer surface. Possible sources of mass loss that are missing from the direct method are basal melt, internal melt, and ablation on crevasse walls. Possible systematic measurement errors include under-estimation of the density of lost material, sinking stakes, or poorly represented areas.  相似文献   

Measurement of Kodaikanal White-Light Images – II. Rotation Comparison and Merging with Mount Wilson Data     

Howard  Robert F.  Gupta  S.S.  Sivaraman  K.R. 《Solar physics》1999,186(1-2):25-41

Sunspot umbral positions and areas were measured for 82 years (1906–1987) of daily, full-disk photoheliogram observations at the Kodaikanal station of the Indian Institute of Astrophysics. The measurement technique and reduction procedures used were nearly identical to those used earlier for the reduction of Mount Wilson daily full-disk photoheliograms, covering an overlapping interval of 69 years. In this paper we compare the differential rotation of the Sun from the analysis of the Kodaikanal data with the Mount Wilson results. In addition, we analyze the data set formed by combining the data from the two sites for differential rotation. While doing this, it has become apparent to us that small, subtle optical effects at both sites produce systematic errors that have an influence on rotation (and other) results from these data. These optical effects are analyzed here, and corrections are made to the positional data of the sunspots from both sites. A data set containing the combined positional data of sunspots from both sites, corrected for these optical aberrations, has been constructed. Results for both sunspot groups and individual sunspots are presented. It is pointed out that optical aberrations similar to those found in the Kodaikanal data may also exist in the Greenwich photoheliograph data, because these two sets of solar images were made with similar telescopes.  相似文献   

Measurement of Kodaikanal white-light images – IV. Axial Tilt Angles of Sunspot Groups     

Sivaraman  K.R.  Gupta  S.S.  Howard  Robert F. 《Solar physics》1999,189(1):69-83

The Kodaikanal sunspot data set, covering the interval 1906–1987, is used in conjunction with the similar Mount Wilson sunspot data set, covering the interval 1917–1985, to examine characteristics of sunspot group axial tilt angles. Good agreement is demonstrated between various results derived from the two independent data sets. In particular, the tendency for sunspot groups near the average tilt angle to be larger than those far from the average tilt angle is confirmed. Similarly the faster residual rotation rate for groups near the average tilt angle is also confirmed. Other confirmations are made for the relationships between latitude drift of sunspot groups and tilt angle, polarity separations, and axial expansion. Evidence is presented that tilt angles averaged over these long time intervals differ between the north and south hemispheres by about 1.4 deg. It is suggested that residual tilt angles show a slight systematic variation with phase in the activity cycle.  相似文献   

Sinusoidal variables from the Tycho Epoch Photometry Annex     

Chris Koen  Robert Schumann 《Monthly notices of the Royal Astronomical Society》1999,310(3):618-628

The Tycho Epoch Photometry Annex A, a data base of photometry of more than 34 000 bright stars, has been searched for periodic variable stars with approximately sinusoidal light curves. Advantage was taken of special properties of the observing programme (photometry in two wavebands, availability of repeated measurements) to use simple but efficient variable selection criteria. Details of 70 strong candidate variables are presented.  相似文献