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51.
Solar Physics - We study a quiet-Sun blowout jet which was observed on 2014 May 16 by the instruments on board the Solar Dynamics Observatory (SDO). We find the twin CME as jet-like and bubble-like... 相似文献
52.
Airborne laser scanning (ALS) is an active remote sensing technique providing range data as 3D point clouds. This paper aims at presenting a survey of the literature related to such techniques, with emphasis on the new sensors called full-waveform lidar systems. Indeed, an emitted laser pulse interacts with complex natural and man-made objects leading to a temporal distortion of the returned energy profile. The new technology of full-waveform laser scanning systems permits one to digitize the complete waveform of each backscattered pulse. Full-waveform lidar data give more control to an end user in the interpretation process of the physical measurement and provide additional information about the structure and the physical backscattering characteristics of the illuminated surfaces. In this paper, the theoretical principles of full-waveform airborne laser scanning are first described. Afterwards, a review of the main sensors as well as signal processing techniques are presented. We then discuss the interpretation of full-waveform measures with special interest on vegetated and urban areas. 相似文献
53.
Direct measurements of plasma motions in the photosphere are limited to the line-of-sight component of the velocity. Several algorithms have therefore been developed to reconstruct the transverse components from observed continuum images or magnetograms. We compare the space and time averages of horizontal velocity fields in the photosphere inferred from pairs of consecutive intensitygrams by the LCT, FLCT, and CST methods and the DeepVel neural network in order to identify the method that is best suited for generating synthetic observations to be used for data assimilation. The Stein and Nordlund (Astrophys. J. Lett.753, L13, 2012) magnetoconvection simulation is used to generate synthetic SDO/HMI intensitygrams and reference flows to train DeepVel. Inferred velocity fields show that DeepVel performs best at subgranular and granular scales and is second only to FLCT at mesogranular and supergranular scales. 相似文献
54.
Light curve modeling for the newly discovered super contact low-mass WUMa system 1SWASPJ092328.76+435044 was carried out by using a new BVR complete light curves. A spotted model was applied to treat the asymmetry of the light curves. The output model was obtained by means of Wilson–Devinney code, which reveals that the massive component is hotter than the less massive one with about ΔT ~ 40 K. A total of six new times of minima were estimated. The evolutionary state of the system components was investigated based on the estimated physical parameters. 相似文献
55.
56.
K. Andrée 《International Journal of Earth Sciences》1916,6(7-8):351-397
Ohne Zusammenfassung 相似文献
57.
Discontinuous Galerkin numerical simulations of single phase flow problem are described in this paper. The simulations show the advantages of using discontinuous approximation spaces. hp convergence results are obtained for smooth solutions. Unstructured meshes and unsmooth solutions are also considered. 相似文献
58.
Márton Pécsi 《GeoJournal》1995,36(2-3):117-131
In the process of loessification, the development of loess fabric, the role of zonal, regional and partly of local environmental factors is regarded decisive. In the loess sequences various genetic types of loess pockets and paleosols occur and reflect different climatic and paleogeographical conditions.As a consequence, even within a single profile the colour, grain size and mineral composition, CaCO3 content, degree of weathering and fabric of loess may vary. Zonal, regional or even local variations in such loess properties may equally derive from syngenetic or postgenetic processes. For similar reasons, spatially and temporally different forms, types and subtypes of paleosol also developed.This way, loess and soil formation resulted in various spatial types in the same glacial, interstadial or interglacial phase in the various geographical zones and regions. Although there exist major loess regions where the interglacial soils (eg brown forest soils) are markedly distinct from interstadial steppe soils or from other types of humic soils, continental loess areas can also be observed where the paleosols developed under interglacial and interstadial conditions (eg steppe or forest steppe soils) cannot be referred into different genetic types. In such cases the changes in paleoenvironments are difficult and uncertain to reconstruct.The interregional correlation of paleosols is occasionally hindered by the various terminologies applied to denote them. In addition, there are uncertainties concerning the dating and identification of paleoenvironments of polygenetic soils and of soil complexes consisting of paleosol units: how many soil formation phases they represent and how long erosional gaps can be reckoned with between these phases. 相似文献
59.
Due to its physical and chemical properties, areas with a loess mantle of proper thickness favour arable farming. Loess as a parent material promotes the formation of soils of good structure, nutrient supply and water budget. The ongoing land evaluation project places particular emphasis on the consideration of parent material in its scoring system as soil and climatic parameters are assessed in conjunction with the grain size composition of subsurface material and soil texture.A test area most suitable for the presentation of the method seems to be a sandy alluvial fan with loess mantle and this circumstance allows the contrasting of the agroecological potentials of soils developed on the two parent materials of different nature.The favourable water storage properties of loess make this deposit particularly valuable under the conditions of climatic aridification. The geographical information system applied here is capable of simulating the agroecological potential changes caused by reduced precipitation, increased evaporation and dropping groundwater levels.The research for this paper was carried out as part of the MEDALUS II (Mediterranean Desertification and Land Use) collaborative research project. MEDALUS II was funded by the EC under its Environment Progamme, contract no. EV5V 0128/0166. A grant was also provided by the OTKA (Hungarian National Science Foundation), project no 1278. The support is gratefully acknowledged. 相似文献
60.
P. Schmidt-Thomé 《International Journal of Earth Sciences》1954,42(2):172-187
Zusammenfassung Klufttektonische Untersuchungen in den Alpen sind spärlich. Nur die Arbeiten aus den bayerischen Kalkalpen lohnen eine vergleichende Betrachtung. Die in nichtalpinen Gebirgen zu Beginn der Faltung auftretenden kubischen Zerrungs-Kluftsysteme lassen sich in den nördlichen Kalkalpen nicht erkennen. Dort treten statt dessen Scherkluftsysteme auf, teils als gekreuzte Systeme, teils als Begleitklüfte streichender Störungen. Unbeeinflußt ziehen sie über Falten- und Deckenstrukturen hinweg, sind also jünger als diese. Das Diagonalkluftsystem geht auf seitliche Spannungen infolge Horizontalbeanspruchung zurück, die gegen Norden gerichtet war. Die Schernatur kommt in der vorwiegend horizontalen Striemung zum Ausdruck. Ein Vergleich mit den offenbar aus Scherklüften hervorgegangenen Diagonalstörungen, die mit den Klüften annähernd gleich alt sind, macht es wahrscheinlich, daß in Südbayern die Einbeziehung der Molasse in den Faltenbau jünger ist als die Diagonalstörungen. Scherkluftsystem und Diagonal-Blattverschiebungen sind für die nördlichen Kalkalpen mit ihrem flachen, nordvergenten Deckenbau besonders bezeichnend und scheinen in zentralen oder westlicheren Alpengebieten zurückzutreten oder ganz zu fehlen. 相似文献