The Experts below are selected from a list of 261 Experts worldwide ranked by ideXlab platform
P V Straznicky - One of the best experts on this subject based on the ideXlab platform.
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magnetic signature attenuation of an unmanned aircraft system for Aeromagnetic Survey
IEEE-ASME Transactions on Mechatronics, 2014Co-Authors: Robert Forrester, Mojtaba Ahmadi, P V StraznickyAbstract:A novel magnetic signature attenuation technique based on reconfiguring the location and orientation of the onboard magnetic sources of an unmanned aircraft system (UAS) is presented in this paper. The UAS, GeoSurv II, is intended for high-resolution Aeromagnetic Survey which requires the magnetic signature of the aircraft to be very low. Genetic algorithm (GA) is used to find an optimum configuration given multiple objective functions motivated by the application. The magnetic field contribution from a single servomotor onboard GeoSurv II is modeled as a single permanent magnet dipole, which is then used to build the cost function for the GA routine. The optimization/simulation outcome suggests very little alteration in the current configuration of the GeoSurv II servomotors resulting in a substantial improvement of the overall magnetic signature of the UAS. The simulation results are validated by practical experimentation. The experimental results, in addition to the simulation results, further confirm that the GA optimized configuration substantially outperforms the current configuration in terms of magnetic signature of GeoSurv II.
Thorkild M. Rasmussen - One of the best experts on this subject based on the ideXlab platform.
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Aeromagnetic Survey in central West Greenland: project Aeromag 2001
GEUS Bulletin, 2002Co-Authors: Thorkild M. RasmussenAbstract:NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article. Rasmussen, T. M. (1). Aeromagnetic Survey in central West Greenland: project Aeromag 2001. Geology of Greenland Survey Bulletin, 191, 67-72. https://doi.org/10.34194/ggub.v191.5130 The series of government-funded geophysical Surveys in Greenland was continued during the spring and summer of 2001 with a regional Aeromagnetic Survey north of Uummannaq, project Aeromag 2001 (Fig. 1). The Survey added about 70 000 line kilometres of high-quality magnetic measurements to the existing database of modern airborne geophysical data from Greenland. This database includes both regional high-resolution Aeromagnetic Surveys and detailed Surveys with combined electromagnetic and magnetic airborne measurements.
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Aeromagnetic Survey in southern West Greenland: project Aeromag 1999
GEUS Bulletin, 2000Co-Authors: Thorkild M. Rasmussen, Inglefield Land, Aem Greenland, Washington Land, East Peary LandAbstract:The acquisition of public airborne geophysical data from Greenland that commenced in 1992 continued in 1999 with project Aeromag 1999, an Aeromagnetic Survey of part of southern West Greenland. This paper presents results of the Aeromagnetic Survey and discusses the correlation of the measured data with the previously mapped surface geology.
Ayako Okubo - One of the best experts on this subject based on the ideXlab platform.
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Magnetization intensity mapping on Unzen Volcano, Japan, determined from high-resolution, low-altitude helicopter-borne Aeromagnetic Survey, Earth Planets Space
2016Co-Authors: Ayako Okubo, Yoshikazu Tanaka, Mitsuru Utsugi, Naoto Kitada, Hiroshi Shimizu, Takeshi MatsushimaAbstract:at two flight altitudes, using spiral trajectories for the first time, over Unzen Volcano in the framework of the Unzen Scientific Drilling Project (USDP). This study obtained more detailed and new information than the previous Aeromagnetic studies in Unzen volcano about the geological features, for understanding the history and eruption mechanism of the Unzen volcano. Therefore, we conducted a magnetization intensity mapping on the volcano, on the assumption that the magnetic anomalies are caused by the terrain magnetized in the same direction as the present Earth’s magnetic field and the magnetization intensity varies only laterally. This map shows good agreement with the geologic features, especially the hydrothermal alteration zone and the collapsed pyroclastic deposits. In addition, even in the area covered by lavas, the magnetization intensities show various values corresponding to each eruption event. It may be considered that the differences in magnetic properties reflect different oxygen fugacity in rocks during their cooling time period. Local magnetization lows on Heisei-Shinzan suggest that the Heisei lava produced by the 1991–1995 eruption has not yet been cooled enough. Key words: Aeromagnetic Survey, Unzen volcano, magnetization intensity mapping. 1
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Apparent magnetization intensity map on Sakurajima Volcano, Kyushu, Japan, inferred from low-altitude, high-density helicopter-borne Aeromagnetic Surveys
Tectonophysics, 2009Co-Authors: Ayako Okubo, Yoshikazu Tanaka, Mitsuru Utsugi, Wataru Kanda, Kazuhiro Ishihara, Daisuke Miki, Tetsuro Takayama, Masayo FukushimaAbstract:Abstract In November 2005, we conducted the first low-altitude, high-density helicopter-borne Aeromagnetic Survey over Sakurajima Volcano, Kyushu, Japan to provide a baseline for subsequent measurement of changes in magnetic anomalies related to volcanic processes, because previously acquired Aeromagnetic data cannot resolve small-scale geological feature. Although the observation error was considered to be 5.0 A/m) were located on the lava around An'ei craters and on the northeastern flank of Kita-dake, (2) the lowermost values of apparent magnetization (
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magnetization intensity mapping on unzen volcano japan determined from high resolution low altitude helicopter borne Aeromagnetic Survey
Earth Planets and Space, 2005Co-Authors: Ayako Okubo, Yoshikazu Tanaka, Mitsuru Utsugi, Naoto Kitada, Hiroshi Shimizu, Takeshi MatsushimaAbstract:On September 18, 2002, we conducted a high-resolution, low-altitude helicopter-borne Aeromagnetic Survey at two flight altitudes, using spiral trajectories for the first time, over Unzen Volcano in the framework of the Unzen Scientific Drilling Project (USDP). This study obtained more detailed and new information than the previous Aeromagnetic studies in Unzen volcano about the geological features, for understanding the history and eruption mechanism of the Unzen volcano. Therefore, we conducted a magnetization intensity mapping on the volcano, on the assumption that the magnetic anomalies are caused by the terrain magnetized in the same direction as the present Earth’s magnetic field and the magnetization intensity varies only laterally. This map shows good agreement with the geologic features, especially the hydrothermal alteration zone and the collapsed pyroclastic deposits. In addition, even in the area covered by lavas, the magnetization intensities show various values corresponding to each eruption event. It may be considered that the differences in magnetic properties reflect different oxygen fugacity in rocks during their cooling time period. Local magnetization lows on Heisei-Shinzan suggest that the Heisei lava produced by the 1991–1995 eruption has not yet been cooled enough.
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High-Resolution, Low-Altitude Helicopter-Borne Aeromagnetic Survey over Unzen Volcano
2004Co-Authors: Ayako Okubo, Yoshikazu Tanaka, Mitsuru Utsugi, Naoto Kitada, Hiroshi Shimizu, Tekeshi MatsushimaAbstract:On September 18, 2002, we conducted a high-resolution, low-altitude helicopter-borne Aeromagnetic Survey over Unzen Volcano. Therefore, we conducted a magnetization intensity mapping on the volcano, on the assumption that the magnetic anomalies are caused by the terrain magnetized in the same direction as the present Earth's magnetic field and the magnetization intensity varies only laterally. This map shows good agreement with the geologic features, especially the hydrothermal alteration zone and the collapsed pyroclastic deposits. In addition, even in the area covered by lavas, the magnetization intensities show various values corresponding to each eruption event. Local magnetization lows on Heisei-Shinzan suggest that the Heisei lava produced by the 1991-1995 eruption has not yet been cooled enough.
Robert Forrester - One of the best experts on this subject based on the ideXlab platform.
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magnetic signature attenuation of an unmanned aircraft system for Aeromagnetic Survey
IEEE-ASME Transactions on Mechatronics, 2014Co-Authors: Robert Forrester, Mojtaba Ahmadi, P V StraznickyAbstract:A novel magnetic signature attenuation technique based on reconfiguring the location and orientation of the onboard magnetic sources of an unmanned aircraft system (UAS) is presented in this paper. The UAS, GeoSurv II, is intended for high-resolution Aeromagnetic Survey which requires the magnetic signature of the aircraft to be very low. Genetic algorithm (GA) is used to find an optimum configuration given multiple objective functions motivated by the application. The magnetic field contribution from a single servomotor onboard GeoSurv II is modeled as a single permanent magnet dipole, which is then used to build the cost function for the GA routine. The optimization/simulation outcome suggests very little alteration in the current configuration of the GeoSurv II servomotors resulting in a substantial improvement of the overall magnetic signature of the UAS. The simulation results are validated by practical experimentation. The experimental results, in addition to the simulation results, further confirm that the GA optimized configuration substantially outperforms the current configuration in terms of magnetic signature of GeoSurv II.
Ginette Saracco - One of the best experts on this subject based on the ideXlab platform.
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Identification of sources of potential fields with the continuous wavelet transform: Basic theory
Journal of Geophysical Research : Solid Earth, 1999Co-Authors: Frédérique Moreau, Dominique Gibert, Matthias Holschneider, Ginette SaraccoAbstract:The continuous wavelet transform is used to analyze potential fields and to locate their causative sources. A particular class of wavelets is introduced which remains invariant under the action of the upward continuation operator in potential field theory. These wavelets make the corresponding wavelet transforms easy to analyze and the sources' parameters (horizontal location, depth, multipolar nature, and strength) simple to estimate. Practical issues (effects of noise, choice of the analyzing wavelet, etc.) are addressed. A field data example corresponding to a near-surface magnetic Survey is discussed. Applications to the high-resolution Aeromagnetic Survey of French Guyana will be discussed in the next paper of the series.