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Research Vessels of the Past and Present—A Brief History of Seagoing Science
Published in George A. Maul, The Oceanographer's Companion, 2017
So are these or any other ships of discovery properly called oceanographic research vessels (RVs)? Little was quantified about Earth before Greek philosophers took to drawing fairly accurate coastline maps, such as shown in Figure 1.1. Earlier examples of map-making date to the Babylonians; Sargon of Akkad (ca. 2300 bc) seems to have predated Greek ideas of a flat Earth surrounded by ΩKEANO∑ (Oceanus) as also proposed by Homer (ca. 850 bc). Yet it was Thales of Miletus (ca. 585 bc) who understood Earth to be a sphere and invented the gnomonic projection (Figure 7.1) to map a sphere on a flat surface. The projection of Figure 1.1 is unknown, but clearly information gathered by ships and sailors with an understanding of latitude and longitude was a research effort.
Chapter 6
Published in Pearson Frederick, Map Projections:, 2018
The characteristic that all great circles appear as straight lines in gnomonic projection has led to the use of this projection in navigation. Refer again to Figure 3. On this figure, the great circle distance between points P1 and P2 is given. The loxodrome is also shown. The great circle is a straight line, but not to true scale. The loxodrome appears as a curved line. As on the sphere itself, the loxodrome is longer than the great circle distance. Compare Figure 3 to Figure 6, Chapter 5, for the equatorial Mercator projection. Recall that the loxodrome on the equatorial Mercator projection appears straight and shorter and the great circle distance appears curved and longer.
A news picture geo-localization pipeline based on deep learning and street view images
Published in International Journal of Digital Earth, 2022
Tianyou Chu, Yumin Chen, Heng Su, Zhenzhen Xu, Guodong Chen, Annan Zhou
This paper used 833,664 perspective images projected from 34,736 Google Street View equirectangular panoramas of the Hong Kong area as a reference dataset, as shown in Figure 1(a). Panoramas with a 2:1 aspect ratio are transformed into perspective images by gnomonic projection. Figure 1(b) displays the local distribution of street view images. These images have longitude and latitude information at intervals of 10–12 m and are evenly distributed on the road. As shown in Figure 1(c), each 3,332 × 1,666 pixel panorama is split into 24 perspective images of 640 × 480 pixels with 12 yaw directions (45° intervals [0, 45, 90, … , 315°]), 60° horizontal field of view (FOV) and 5°, 20°, 35° pitch directions. The perspective images overlap each other by approximately 80%.
Confessionalization and comets. John Bainbridge on the comet of 1618
Published in Annals of Science, 2022
The astronomical part appears primarily directed to a lay audience, although a highly educated one, not to fellow astronomers or mathematicians, as is clear from the elementary level of his explanations. In particular, there is a very long explanation of the principles of parallax measurements, including a diagram (14–19; the actual observations are described on p. 19–20). Still, Bainbridge emphasizes his mathematical proficiency. At the core of his work is a ‘celestiall Planispheare’ (2), a map of the sky depicting the comet's course. Bainbridge uses a gnomonic projection to depict the celestial sphere, which he calls a ‘new manner’ which he ‘specially invented’. (2–3, 8) Actually, Kepler had already used such a projection in his treatise on the new star of 1604, published at Prague in 1606.15 Given what we know of Bainbridge's intellectual network in London, it is hard to believe that he was not aware of that.
Paleomagnetism of the Carboniferous Gresford Block, Tamworth Belt, southern New England Orogen: minor counter-clockwise rotation of a primary arc segment
Published in Australian Journal of Earth Sciences, 2020
Thermal demagnetisation results show well-defined, reverse polarity, site-mean poles for the 12 sites from the main flow unit (Table 2: 7–18), with the 12 poles showing a substantial girdle-like spread (Figure 16a) that is comparable with Rouchel Block results (Klootwijk, 2016, figure 12j) for the MCIM. Three sites from the base of the MCIM, from tuffs below and different from the main flow unit (Table 1: 4–6), show normal polarity site-mean poles that are well removed from the group of 12 reverse polarity poles and agree with Permo-Triassic overprint poles observed herein (Figure 18f; Table S8) and in other TB blocks. A duplicate collection of MCIM specimens that have been LN-treated prior to thermal demagnetisation shows a slightly tighter distribution of reverse polarity site-mean poles (Figure 16b; Table 2: 9–18). The distribution of reverse polarity site-mean poles for integrated thermal and LN-pre-treated thermal results (Figure 16c1; Table 2: 7–18) is comparable with the spread of likewise-integrated reverse polarity MCIM site-mean poles for the Rouchel Block (Figure 16d1), although most of the Gresford Block poles concentrate slightly better than most of the Rouchel Block poles (Figure 16a–d). The girdle-like spread of integrated site-mean poles for the Gresford Block, shown in aitoff projection (Figure 16c1), shows up less pronounced in gnomonic projection (Figure 16c2)6, indicating elliptical distortion in far off-centre parts of the, whole-world, aitoff projection. Gnomonic projection of site-mean directions (Figure 16c3) rather than site-mean poles (Figure 16c2) again shows a far lesser girdle-like spread, indicating that the girdle-like spread in site-mean poles (Figure 16c1) is largely attributable to the combined effects of direction-to-pole transformation and elliptical distortion in aitoff projection.