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Results of three-colour VRI CCD photometry are presented obtained during 11 nights in 2001. Twelve new minima timings are derived. The eclipse depth decreases with wavelength, being equal to 1.28, 1.13 and 1.02 for V, R and I, respectively. The instrumental magnitudes and colours are tabulated for the mid-eclipse, out-of-eclipse part and the eclipsed component. The VR colour of the eclipsed component of emission is by 0.22 mag bluer than that for mid-eclipse, indicating a much higher temperature of the eclipsed region.  相似文献   
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The Upper Selemdzha minerogenic zone, which has the potential for noble metal mineralization in the Upper Amur, has been studied. It is confined to the thick strata of Paleozoic terrigeneous-sedimentary rocks (sandstones, siltstones, clay schists, packages of their thin rhythmical interlayering, sedimentary breccias, and conglomerates) in the Tokura subzone of the Selemdzha-Kerbinsk zone in the Amur-Okhotsk area of the Mongol-Okhotsk system, overlain by Early Cretaceous volcanogenic sedimentary rocks and intruded by Early Cretaceous quartz diorites, granodiorites, and dacites. In the Malomyr and Sagur-Semertak ore clusters, there are a few known potential deposits of noble metals and ore occurrences; when studied and prospected, they can exhibit vein-veinlet noble metal mineralization with rich contents of gold and platinoids in ore columns and metasomatic deposits.  相似文献   
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-The North Channel in the Yangtze Estuary is one of sea-leading waterways of Shanghai Harbour, in which yearly dredging volume reaches over ten million cubic meters, and it tends to increase year by year. Based on the channel regime similarity and through the relational grade, a GM (2, 1) is set up. It reveals the course of development of channel regime similarity under the action of various factors, and predicts the siltation volume in the nearest future which is the basis of dredging planning for relevant dredging departments.  相似文献   
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????CNES???????????????????λ???????д?????????????????о????????????????????????????????????????????????CNES??????????????????SuomiNet????????????????IGS??????????????????????????????????????????????????к???????  相似文献   
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Macroalgae plays an important role in coastal ecosystems. The accurate delineation of macroalgae areas is important for environmental management. This study compared the pixel- and object-based methods using Gaofen satellite no. 2 image to explore an efficient classification approach. Expert system rules and nearest neighbour classifier were adopted for object-based classification, whereas maximum likelihood classifier was implemented in the pixel-based approach. Normalized difference vegetation index, normalized difference water index, mean value of the blue band and geometric characteristics were selected as features to distinguish macroalgae farms by considering the spectral and spatial characteristics. Results show that the object-based method achieved a higher overall accuracy and kappa coefficient than the pixel-based method. Moreover, the object-based approach displayed superiority in identifying Porphyra class. These findings suggest that the object-based method can delineate macroalgae farming areas efficiently and be applied in the future to monitor the macroalgae farms with high spatial resolution imagery.  相似文献   
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Churkin  K. O.  Nefedyev  Yu. A.  Andreev  A. O.  Demina  N. Yu.  Kronrod  E. V. 《Astronomy Reports》2021,65(7):580-587
Astronomy Reports - One of the priority tasks of modern astronomy is the observation and study of transient celestial processes, which also concerns photoelectric observations of lunar occultations...  相似文献   
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