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采用广义点摄影测量理论对建筑物立面框架轮廓进行重构。广义点是对当代线摄影测量以及无穷远点（灭点）理论的升华。实验结果表明,采用线面基元进行立面重构相比于经典的点云重构方法,不仅简洁、高效,还能获得清晰的三维边缘轮廓,且自动化程度较高。 相似文献
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矿体产于白垩纪马头窝单元（K1^7M^λπ）石英斑岩与石炭系上统空树河组三段二层（C2k^3-3）地层的石英砂岩、长石石英砂岩接触带上,或上述两类岩石的破碎带中,矿体与围岩界线常呈波状起伏,呈突变或渐变接触。矿区围岩蚀变明显,有进一步找矿的前景。 相似文献
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Vršnak B. Roša D. Božić H. Brajša R. Ruždjak V. Schroll A. Wöhl H. 《Solar physics》1999,185(2):207-225
Two large stable solar filaments were used as test tracers to determine the apparent synodic rotation rate as a function of the central meridian distance for several filaments' segments at different heights. An analytic fitting procedure was applied to determine simultaneously the real synodic rotation rate and the height of the traced filament segments. The determined heights were compared with the values obtained from the widths of filament contours on the solar disk and with the values obtained by direct measurements at the solar limb. Furthermore, the obtained rotation rates and heights of the filaments' segments close to the filaments' pivot points were compared with the values obtained using two successive central meridian passages. Finally, sources and scales of errors were investigated and possible implications on the previous studies of the solar differential rotation were considered. 相似文献
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Terra rossa and eutric cambisol soils were surveyed in Slovenia. At both sites, 6–13 boreholes were drilled in a regular 24 m × 24 m
square grid. Soil samples from various depths were taken for gamma spectrometric analysis, and radon in soil gas was measured
at a depth of 80 cm using an AlphaGuard instrument. The following ranges of activity concentration (Bq kg−1) were obtained for 238U, 226Ra, 228Ra, 40K and 137Cs: in terra rossa, 64–74, 70–84, 45–49, 293–345, 20–30 and, in eutric cambisol, 55–80, 132–147, 50–57, 473–529, 106–272.
Radon activity concentrations in both soils ranged from about 100 kBq m−3 to 370 kBq m−3. 相似文献
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The Julian Alps are located in NW Slovenia and structurally belong to the Julian Nappe where the Southern Alps intersect with
the Dinarides. In the Jurassic, the area was a part of the southern Tethyan continental margin and experienced extensional
faulting and differential subsidence during rifting of the future margin. The Mesozoic succession in the Julian Alps is characterized
by a thick pile of Upper Triassic to Lower Jurassic platform limestones of the Julian Carbonate Platform, unconformably overlain
by Bajocian to Tithonian strongly condensed limestones of the Prehodavci Formation of the Julian High. The Prehodavci Formation
is up to 15 m thick, consists of Rosso Ammonitico type limestone and is subdivided into three members. The Lower Member consists
of a condensed red, well-bedded bioclastic limestone with Fe–Mn nodules, passing into light-grey, faintly nodular limestone.
The Middle Member occurs discontinuously and consists of thin-bedded micritic limestone. The Upper Member unconformably overlies
the Lower or Middle Members. It is represented by red nodular limestone, and by red-marly limestone with abundant Saccocoma sp. The Prehodavci Formation unconformably overlies the Upper Triassic to Lower Jurassic platform limestone of the Julian
Carbonate Platform; the contact is marked by a very irregular unconformity. It is overlain by the upper Tithonian pelagic
Biancone (Maiolica) limestone. The sedimentary evolution of the Julian High is similar to that of Trento Plateau in the west
and records: (1) emergence and karstification of part of the Julian Carbonate Platform in the Pliensbachian, or alternatively
drowning of the platform and development of the surface by sea-floor dissolution; (2) accelerated subsidence and drowning
in the Bajocian, and onset of the condensed pelagic sedimentation (Prehodavci Formation) on the Julian High; (3) beginning
of sedimentation of the Biancone limestone in the late Tithonian. 相似文献
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D. Maričić B. Vršnak M. Dumbović T. Žic D. Roša D. Hržina S. Lulić I. Romštajn I. Bušić K. Salamon M. Temmer T. Rollett A. Veronig N. Bostanjyan A. Chilingarian B. Mailyan K. Arakelyan A. Hovhannisyan N. Mujić 《Solar physics》2014,289(1):351-368
We study heliospheric propagation and some space weather aspects of three Earth-directed interplanetary coronal mass ejections (ICMEs), successively launched from the active region AR 11158 in the period 13?–?15 February 2011. From the analysis of the ICME kinematics, morphological evolution, and in situ observations, we infer that the three ICMEs interacted on their way to Earth, arriving together at 1 AU as a single interplanetary disturbance. Detailed analysis of the in situ data reveals complex internal structure of the disturbance, where signatures of the three initially independent ICMEs could be recognized. The analysis also reveals compression and heating of the middle ICME, as well as ongoing magnetic reconnection between the leading and the middle ICME. We present evidence showing that the propagation of these two, initially slower ICMEs, was boosted by the fastest, third ICME. Finally, we employ the ground-based cosmic ray observations, to show that this complex disturbance produced a single cosmic ray event, i.e., a simple Forbush decrease (FD). The results presented provide a better understanding of the ICME interactions and reveal effects that should be taken into account in forecasting of the arrival of such compound structures. 相似文献
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Existing methods for conversion between synodic and sidereal rotation velocities of the Sun are tested for validity using state-of-the-art ephemeris data. We found that some of them agree well with ephemeris calculations while others show a discrepancy of almost 0.01° day?1. This discrepancy is attributed to a missing factor and a new corrected relation is given. 相似文献
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Brajša R. Wöhl H. Vršnak B. Ruždjak D. Sudar D. Roša D. Hržina D. 《Solar physics》2002,206(2):229-241
Stable recurrent sunspot groups from the Greenwich data set which were identified in at least two subsequent solar rotations were traced. The solar rotation was determined by the period method from the time difference of the two central meridian passages of each of the 327 identified groups. Sidereal rotation periods were calculated from the synodic ones by a seasonal-dependent procedure taking into account the details of the Earth's motion around the Sun. Growing recurrent sunspot groups rotate on the average faster than decaying recurrent sunspot groups, while sunspot groups of all types taken together rotate faster than both growing and decaying recurrent sunspot groups. A north–south rotational asymmetry and a cycle-dependence of rotational velocity of recurrent sunspot groups were analyzed. Positive rotation velocity deviations are larger, but less numerous than the negative ones. Signatures of torsional oscillations were not found analyzing the rotation velocity residual of recurrent sunspot groups as a function of the distance from the average latitude of activity. 相似文献
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LIU Shaochuang LU Pingli LIU Donghui JIN Peidong Institute of Remote Sensing Applications Chinese Academy of Sciences Datun Road Chaoyang District Beijing China. 《地球空间信息科学学报》2007,10(1):51-56
For centuries, explorers and scientists from different countries had made their own conclusions on the source of the Mekong. However, the geographic source of the Mekong is still arguable because of the complexity of the Mekong source water system, inaccessible environment and the varied technologies used by those explorers and scientists. The satellite remote sensing technology has been used to pinpoint the source of the Mekong, associated with the on-the-spot investigations made by the authors in June 1999 and September 2002. The actual length of the Mekong has also been calculated. 相似文献