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991.
Izvestiya, Atmospheric and Oceanic Physics - The central part of the Malouralsky volcanic–plutonic belt, which includes the Manyukuyu–Vorchatinsky ore cluster, is analyzed using...  相似文献   
992.
Izvestiya, Atmospheric and Oceanic Physics - Direct numerical simulations of wind-generated gravity waves on a 2D sea surface are carried out within the framework of the basic potential equations...  相似文献   
993.
Solar System Research - This article describes the results of the Phobos 2 interplanetary mission, launched in 1988, and presents some prospective scenarios for studying near-Mars space, including...  相似文献   
994.
Solar System Research - The article discusses the problems of controlling the relative motion of spacecraft (SC) in a tandem flight configuration. Flight configurations of two SC that form the...  相似文献   
995.
Dmitriev  D. V.  Grinin  V. P.  Katysheva  N. A. 《Astronomy Letters》2019,45(6):371-383
Astronomy Letters - The formation of hydrogen emission lines in the magnetospheres of young stars is considered. The magnetosphere is assumed to be formed by a dipolar magnetic field whose axis is...  相似文献   
996.
Virtual citizen science platforms allow nonscientists to take part in scientific research across a range of disciplines, including planetary science. What is required of the volunteer can vary considerably in terms of task type, variety, judgment required, and autonomy—even when the overall goal is unchanged. Through analysis of our live Zooniverse Planet Four: Craters citizen science platform, the effects of task workflow design factors including volunteer autonomy, task variety, task type, and judgment required on volunteer engagement and crater marking performance were investigated. Website analytics showed volunteers using the Full interface (most autonomy and variety) were more likely to return to the platform, although the amount of time spent per visit was unaffected by the interface used. However, analysis of performance suggested that how this time was used did differ. The interface involving the least complex task resulted in the greatest amount of data and rate of collection, although this also coincided with a greater number of false positives when compared with the expert. Performance in terms of agreement, both between participants and with the expert judgment, was significantly improved when using the Stepped interface for crater position and the Ramped (Mark) when measuring diameter—interfaces that both directly measured the metric with a specific, delineated task. The implications for planetary scientists considering the citizen science route is that there is a balancing act to perform, weighing the importance of volunteer engagement with scientists' data needs and the resources that can be committed to data validation.  相似文献   
997.
Natural Resources Research - Oil shale impurities prevent its direct usage as a source of energy. Removing or reducing of these impurities before retorting can reduce the cost of oil shale...  相似文献   
998.
Izvestiya, Atmospheric and Oceanic Physics - The results of the fractal analysis of a drainage network reconstructed using a digital elevation model and the structural and geomorphological analysis...  相似文献   
999.
1000.
On the southwest-facing slopes of a bedrock ridge lying between Cardigan Bay to the north and the Afon Teifi to the south stands a group of hills in which 30-35 m of cross-laminated and parallel-laminated sands with lenticular upward-fining gravel sequences are overlain by 10-12 m of gravel in a single foreset bed. The sediments mantle a surface of till sloping gently toward the southwest, were transported toward the southwest (across one margin of the Afon Teifi valley), and were cut by a system of densely arranged conjugate normal faults striking northwest-southeast. The lenticular gravels and fault system suggest that the deposits accumulated as a glaciofluvial outwash spread, and on top of an ice-lobe that became isolated in the Teifi valley during the downwasting of a glacier which had occupied Cardigan Bay and much of the country to the south. The large gravel foresets capping the succession are the only indication at Banc-y-Warren of the former existence of a lake, but neither a large nor deep body of water need be envisaged.  相似文献   
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