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1.
A. Ankilov A. Baklanov M. Colhoun K. -H. Enderle J. Gras Yu. Julanov D. Kaller A. Lindner A. A. Lushnikov R. Mavliev F. McGovern T. C. O'Connor J. Podzimek O. Preining G. P. Reischl R. Rudolf G. J. Sem W. W. Szymanski A. E. Vrtala P. E. Wagner W. Winklmayr V. Zagaynov 《Atmospheric Research》2002,62(3-4)
During an international workshop at the Institute for Experimental Physics of the University of Vienna, Austria, which was coordinated within the Committee on Nucleation and Atmospheric Aerosols (IAMAS-IUGG), 10 instruments for aerosol number concentration measurement were studied, covering a wide range of methods based on various different measuring principles. In order to investigate the detection limits of the instruments considered with respect to particle size, simultaneous number concentration measurements were performed for monodispersed aerosols with particle sizes ranging from 1.5 to 50 nm diameter and various compositions.The instruments considered show quite different response characteristics, apparently related to the different vapors used in the various counters to enlarge the particles to an optically detectable size. A strong dependence of the 50% cutoff diameter on the particle composition in correlation with the type of vapor used in the specific instrument was found. An enhanced detection efficiency for ultrafine hygroscopic sodium chloride aerosols was observed with water operated systems, an analogous trend was found for n-butanol operated systems with nonhygroscopic silver and tungsten oxide particles. 相似文献
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Anabele Lindner Cira Souza Pitombo Samille Santos Rocha José Alberto Quintanilha 《地球空间信息科学学报》2016,19(4):245-254
Studies in transportation planning routinely use data in which location attributes are an important source of information. Thus, using spatial attributes in urban travel forecasting models seems reasonable. The main objective of this paper is to estimate transit trip production using Factorial Kriging with External Drift (FKED) through an aggregated data case study of Traffic Analysis Zones in São Paulo city, Brazil. The method consists of a sequential application of Principal Components Analysis (PCA) and Kriging with External Drift (KED). The traditional Linear Regression (LR) model was adopted with the aim of validating the proposed method. The results show that PCA summarizes and combines 23 socioeconomic variables using 4 components. The first component is introduced in KED, as secondary information, to estimate transit trip production by public transport in geographic coordinates where there is no prior knowledge of the values. Cross-validation for the FKED model presented high values of the correlation coefficient between estimated and observed values. Moreover, low error values were observed. The accuracy of the LR model was similar to FKED. However, the proposed method is able to map the transit trip production in several geographical coordinates of non-sampled values. 相似文献
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Ohne Zusammenfassung 相似文献
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The stratigraphy of western Australia 总被引：2，自引：2，他引：0
J. R. H. McWhae P. E. Playford A. W. Lindner B. F. Glenister B. E. Balme 《Australian Journal of Earth Sciences》2013,60(2):1-153
Abstract Measurements of intensity of magnetization and susceptibility have been made at intervals of 5 ft. on some bore cores from Tasmanian tholeiites of Jurassic age. In all cases the direction of magnetization was nearly vertical. One sill appears to have its upper 700 ft. magnetized normally and its lower part reversed. The magnetic properties vary very rapidly and show a structure in which narrow regions with high values are superposed on a general increase to a maximum at about 300 ft. from the top of the sill. This coincides with a minimum of the density and a maximum of normative magnetite and total iron and also in the size of the areas of mesostasis. It is suggested that this behaviour is due to differentiation and that magnetic measurements form an extremely sensitive tool for the study of this process. An attempt is made to show that differentiation by the settling of individual crystals through the sill is impossible in thick sills in which convection does not occur. and that the mechanism must be one of roof stoping in which large blocks of mixed crystals and residual magma fall from the roof to the floor of the sill. The regions with exceptionally high magnetic values which have been observed are regarded as composed of magma trapped between these blocks. 相似文献
5.
Application of a forest succession model to a continentality gradient through Central Europe 总被引：1，自引：0，他引：1
The forest succession model FORSKA was applied to a west-east transect across Central Europe using points from a global climate data set. Climate change experiments were undertaken for two general circulation model scenarios and two different site classes. The simulated climate changes lead to reduced forest productivity and a changed species composition on most sites. Under current climate, the broad scale pattern of the climatically driven distribution of forest communities is quite realistically reproduced. However, the resolution of climate data imposes limitations on the simulation of forest dynamics in subcontinental climate, because climate variability and extreme events are not well represented. 相似文献
6.
Francis P. Miknis Arthur W. Lindner A. John Gannon Mark F. Davis Gary E. Maciel 《Organic Geochemistry》1984,7(3-4)
Solid state 13C NMR techniques of cross polarization with magic-angle spinning, and interrupted decoupling have been employed to examine the nature of the organic matter in eight kerogen concentrates representing five Tertiary deposits in Queensland, Australia. The NMR results show that five of the kerogens have high proportions of aliphatic carbon in their organic matter and correspond to Type I–II algal kerogens. Three of the kerogens, derived from carbonaceous shales, have a high proportion of aromatic carbon in their organic matter and correspond to Type III kerogens. The fractions of aliphatic carbon in all the kerogens, regardless of type, are shown to correlate with the conversion characteristics of the corresponding raw shales during Fischer assay. Interrupted decoupling NMR results show the presence of more oxygen-substituted carbon in the carbonaceous shales, which may account for the greater CO2 evolution and phenolic materials found in the pyrolysis products of the carbonaceous shales. 相似文献
7.
Peter Lindner 《Geoforum》2007,38(3):494-504
Soviet collectives in general and especially the kolkhozes in rural areas were much more than merely production units. They regulated a significant part of everyday life in the villages and thus have to be seen as all-embracing social institutions, constituting the bedrock for rural communities. Relying on the homogenising effect of the kolkhoz-mechanism most authors who analyse the process of transformation in the Post-Soviet Russian countryside highlight the failures of privatisation and consequently presume continuity and not change. This paper argues, first, that in view of the weakness of the central state in the 90s a considerable leeway existed at the local level for different ways and degrees to implement the reform legislation and, second, that the concrete outcomes of the restructuring can only be adequately understood focusing on interests and power relations on the micro level rather than dealing with farms as such as the ‘acting units’.The common vantage point for most of the kolkhozes was an “alliance for the locale” between management and workers. It had its roots in the fear to become “slaves on one’s own land” if non-local investors would be allowed to buy agricultural land, to remain without infrastructure like streets, water supply and kindergartens if the kolkhoz would be divided up and to lack the machinery to work the private plots without the support of the farms. But beyond this consensus the chairmen of the collective farms could rely on a bulk of different allocative and authoritative resources to stage-manage privatisation. This introduced a highly ‘individual’ moment in the process and led to rising disparities and an increasing disintegration of rural Russia in the 1990s. Using a farm in southern Russia as an example the closer look at these resources and the “failed privatisation” unveils, that not continuity, but hybrid amalgamations of old and new characterise the Post-Soviet Russian countryside. 相似文献
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We investigate the possibility to use the neutrinos coming from a future galactic supernova explosion to perform neutrino oscillation tomography of the Earth’s core. We propose to use existing or planned detectors, resulting in an additional payoff. Provided that all of the discussed uncertainties can be reduced as expected, we find that the average matter densities of the Earth’s inner and outer cores could be measured with a precision competitive with geophysics. However, since seismic waves are more sensitive to matter density jumps than average matter densities, neutrino physics would give partly complementary information. 相似文献
10.
A. Lindner 《Astroparticle Physics》1998,8(4):235-252
A Monte Carlo study to reconstruct energy and mass of cosmic rays with energies above 300 TeV using ground based measurements of the electromagnetic part of showers initiated in the atmosphere is presented. The shower properties determined with two detector arrays measuring the air Cherenkov light and the particle densities as realized at the HEGRA experiment are processed to determine the energy of the primary particle without the need of any hypothesis concerning its mass. The mass of the primary particle is reconstructed coarsely from the same observables in parallel to the energy determination. 相似文献