In consideration of the significance of connectivity features and topological relationships within the pore-crack network, the micro-scale pore-crack microstructure of intact and tectonic coals from Qinan was investig...
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In consideration of the significance of connectivity features and topological relationships within the pore-crack network, the micro-scale pore-crack microstructure of intact and tectonic coals from Qinan was investigated in 3d spatial visualization using digital core technology. The results indicate that the roughly vertical distribution in intact coal microstructure regularly divides the coal matrix into several cubic blocks. Tectonism is responsible for the fundamental transformation of the microstructure, causing tectonic coals to exhibit more sporadically distributed microcracks and pore clusters. The topological sphere and stick model based on skeletonization and its quantitative connectivity parameters show that the throat lengths of Qinan coals are mainly 0-150 mu m, with tectonic coals having fewer throats over 100 mu m. Pore diameters in intact coals are mostly under 30 mu m, while tectonic coals exceed 20 mu m. Compared with intact coals, pore spaces under 2000 mu m(3) in tectonic coals increased from 61.38% to 71.13%, surface area increased from 69.98% to 77.76%, and coordination number also increased significantly. These quantitative parameters collectively indicate that tectonic factors promoted the formation of more minute-scale pore spaces and significantly enhanced the connectivity between pore spaces and throats. On this basis, the pore-scale flow simulations were carried out from the equivalent pore network model, indicating that the pressure distribution of tectonic coals in different directions could be more concentrated and uniform than intact coals with lower fluid pressure values, revealing the promotion of tectonic effects on pore-scale fluid transport.
As various types of information are being created through the recent technical developments in, and use of, smart devices, it is becoming increasingly important to manage spatial information, which is the foundation f...
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ISBN:
(数字)9783030172466
ISBN:
(纸本)9783030172459;9783030172466
As various types of information are being created through the recent technical developments in, and use of, smart devices, it is becoming increasingly important to manage spatial information, which is the foundation for utilizing information. This study defines the characteristics of spatial information, which can be used in the future, and proposes a 3d geospatial grid system (3dGGS) to manage spatial information. Based on a literature review, the characteristics of spatial information, which will be required in the future, are examined. Thus, the concept and characteristics of 3dGGS are presented, based upon which the application scope and rules of 3dGGS are set. In addition, geographic information systems developed by the Rep. of Korea and other countries are analyzed, and an architecture and framework through which 3dGGS can be implemented are presented. Finally, the results of this study are summarized, and areas of future works are introduced.
Researchers have found that 3dspatial skills are critical to success in a variety of careers, particularly in engineering and science. For engineering, the ability to mentally rotate objects in space has been found t...
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Researchers have found that 3dspatial skills are critical to success in a variety of careers, particularly in engineering and science. For engineering, the ability to mentally rotate objects in space has been found to be of particular importance. Unfortunately, of all areas of cognition, 3dspatial skills still exhibit some of the most robust gender differences favouring males, and the most pronounced gender differences are in the area of mental rotations. For this reason, poorly developed3dspatial skills could be a hindrance to the success of women in engineering. University educators are quick to recognise deficiencies in math and chemistry, and many US universities have developed remediation programs for students with weaknesses in these areas. At a time when we are actively recruiting women for engineering programs, however, it is important to consider all possible barriers to their success. At Michigan Technological University (MTU), we have been offering a special course aimed at improving the 3dspatial skills of engineering students, particularly women, since 1993. This paper will summarise the findings obtained over the past decade at MTU in improving the 3dspatial skills of engineering students. The paper will also feature improvements in student success that we have achieved, especially for women, through implementation of this bridging course.
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