scholarly journals ITERATIVE REFINEMENT FOR UNDERWATER 3D RECONSTRUCTION: APPLICATION TO DISPOSED UNDERWATER MUNITIONS IN THE BALTIC SEA

Author(s):  
Y. Song ◽  
K. Köser ◽  
T. Kwasnitschka ◽  
R. Koch

<p><strong>Abstract.</strong> With the rapid development and availability of underwater imaging technologies, underwater visual recording is widely used for a variety of tasks. However, quantitative imaging and photogrammetry in the underwater case has a lot of challenges (strong geometry distortion and radiometry issues) that limit the traditional photogrammetric workflow in underwater applications. This paper presents an iterative refinement approach to cope with refraction induced distortion while building on top of a standard photogrammetry pipeline. The approach uses approximate geometry to compensate for water refraction effects in images and then brings the new images into the next iteration of 3D reconstruction until the update of resulting depth maps becomes neglectable. Afterwards, the corrected depth map can also be used to compensate the attenuation effect in order to get a more realistic color for the 3D model. To verify the geometry improvement of the proposed approach, a set of images with air-water refraction effect were rendered from a ground truth model and the iterative refinement approach was applied to improve the 3D reconstruction. At the end, this paper also shows its application results for 3D reconstruction of a dump site for underwater munition in the Baltic Sea for which a visual monitoring approach is desired.</p>

2012 ◽  
Vol 46 (1) ◽  
pp. 37-50 ◽  
Author(s):  
Victor Zhurbas ◽  
Vadim Paka

AbstractResults of modeling of the migration of chemical warfare agents (CWAs) and their decay products from the initial chemical weapons dump site are presented. The aim was to find idealized sediment redistribution schemes in deep basins of the Baltic Sea corresponding to different wind conditions and to model the concentration of dissolved CWA in a continuous release scenario in the Bornholm dump site corresponding to real wind statistics.


2013 ◽  
Vol 13 (7) ◽  
pp. 1270-1283 ◽  
Author(s):  
Gladys A. Liehr ◽  
Susanne Heise ◽  
Wolfgang Ahlf ◽  
Kristen Offermann ◽  
Gesine Witt

2021 ◽  
Vol 193 (12) ◽  
Author(s):  
Ulrike Kammann ◽  
Marc-Oliver Aust ◽  
Maike Siegmund ◽  
Nicole Schmidt ◽  
Katharina Straumer ◽  
...  

AbstractDumped munitions contain various harmful substances which can affect marine biota like fish. One of them is mercury (Hg), included in the common explosive primer Hg fulminate. There is still a lack of knowledge whether dumped munitions impact the Hg concentrations in the Baltic Sea environment. This study aims to answer the question if dab caught at the dump site Kolberger Heide show higher Hg concentrations released from munition sources and whether Hg in fish is a usable marker for munition exposure. Therefore, a total of 251 individual dab (Limanda limanda) were analysed including 99 fish from the dump site. In fish from the Kolberger Heide, no elevated Hg concentrations were found compared to reference sites when age-dependent bioaccumulation of mercury was considered. Therefore we conclude that Hg in fish is no suitable indicator for exposure to munition dumping, e.g. in the frame of possible future monitoring studies as Hg exposure originating from dumped munition is only a small contributor to overall Hg exposure of fish.


Boreas ◽  
2002 ◽  
Vol 31 (1) ◽  
pp. 65-74 ◽  
Author(s):  
Christian Christiansen ◽  
Helmar Kunzendorf ◽  
Kay-Christian Emeis ◽  
Rudolf Endler ◽  
Ulrich Struck ◽  
...  

2003 ◽  
pp. 136-146
Author(s):  
K. Liuhto

Statistical data on reserves, production and exports of Russian oil are provided in the article. The author pays special attention to the expansion of opportunities of sea oil transportation by construction of new oil terminals in the North-West of the country and first of all the largest terminal in Murmansk. In his opinion, one of the main problems in this sphere is prevention of ecological accidents in the process of oil transportation through the Baltic sea ports.


Author(s):  
Angelina E. Shatalova ◽  
Uriy A. Kublitsky ◽  
Dmitry A. Subetto ◽  
Anna V. Ludikova ◽  
Alar Rosentau ◽  
...  

The study of paleogeography of lakes is an actual and important direction in modern science. As part of the study of lakes in the North-West of the Karelian Isthmus, this analysis will establish the dynamics of salinity of objects, which will allow to reconstruct changes in the level of the Baltic Sea in the Holocene.


Author(s):  
Małgorzata Leśniewska ◽  
Małgorzata Witak

Holocene diatom biostratigraphy of the SW Gulf of Gdańsk, Southern Baltic Sea (part III)The palaeoenvironmental changes of the south-western part of the Gulf of Gdańsk during the last 8,000 years, with reference to the stages of the Baltic Sea, were reconstructed. Diatom analyses of two cores taken from the shallower and deeper parts of the basin enabled the conclusion to be drawn that the microflora studied developed in the three Baltic phases: Mastogloia, Littorina and Post-Littorina. Moreover, the so-called anthropogenic assemblage was observed in subbottom sediments of the study area.


2003 ◽  
pp. 50-61 ◽  
Author(s):  
V. A. Smagin ◽  
M. G. Napreenko

The paper characterizes the 3 associations comprising plant communities with Sphagnum rubellum in the south-eastern part of the Baltic region. The new syntaxa differ from each other both in their floristic characters and the pronounced affinity to definite regional mire types and particular habitats. The ass. Drosero-Sphagnetum rubelli is typical of the relatively most thorough ranges. It is observed from the Kaliningrad region to the Karelian Isthmus and, according to the published reference, occurs even throughout the whole area around the Baltic Sea. Its most typical habitat is that of margins of mire lakes and pools. The ass. Eriophoro-Sphagnetum rubelli occurs in central plateaus of convex plateau-like bogs, typical of the areas adjacent to the Baltic Sea coast. It occupies extended flat mire ecotopes with the water level 0.2–0.25 m deep. The ass. Empetro-Sphagnetum rubelli is characteristic of the retrogressive complex in the convex bogs of the East-Baltic Province. It is mostly observed along the coast of the Gulf of Finland. Its stands are rather dynamic and unstable in both space and time. The presence of communities comprised by these 3 associations is an important vegetation character of the series of regional mire types. Assuming an association level of the respective syntaxa seems rational for the purposes of adequate reflection of plant cover diversity.


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