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Lineaments Extraction and Analysis Using Landsat 8 (OLI/TIRS) in the Northeast of Morocco 被引量:3
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作者 Meryem Redouane Hicham Si Mhamdi +2 位作者 Faouziya Haissen Mohammed Raji Othman Sadki 《Open Journal of Geology》 2022年第5期333-357,共25页
Northeastern Morocco is made up of several units belonging to the Alpine belt and its foreland. Miocene to plio-quaternary volcanic rocks with variable mineralogy and geochemistry dominate the geology of this region. ... Northeastern Morocco is made up of several units belonging to the Alpine belt and its foreland. Miocene to plio-quaternary volcanic rocks with variable mineralogy and geochemistry dominate the geology of this region. The presence of active faults in different directions explains the high tectonic instability and the high frequency of earthquakes. This study contributes to the effort of understanding the geothermal potential of the Northeast of Morocco. Heat source and permeability are both key factors in the geothermal process. Indeed, lineaments analysis constrains the structures and their directions and indicates severely faulted zones, which are the most promising areas for geothermal exploration. For this purpose, we used Landsat data combined with geological and structural maps available in this region. Different image processing techniques were applied including band ratio (6/2) and directional filters. To validate the results, we conducted a comparative study between linear structures, available geological data, and previous studies. Results of the automatic extraction method of lineaments from Landsat 8 OLI/TIRS indicate three main lineament systems: 1) a NE-SW system ranging from N40 to N70;2) an N-S system ranging from N10 to N45;3) an EW to WNW-ESE systems ranging from N80 to N120. Most of lineaments extracted are localized in Kebdana, Amejjaou, Nador and Melilla regions. Compared to previous studies, the NE-SW system is consistent with an extensive period (Tortonian to Pliocene);the NW-SE system is consistent with the last compressive episode (Pliocene);the N-S system is consistent with the first compressive period (Late/End Tortonian). 展开更多
关键词 Northeastern Morocco Rif Belt Faults Miocene-Plio Quaternary Volcanism Permeability LINEAMENTS Landsat 8 (OLI/TIRS)
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Estonia: The Prospects of Nuclear Energy
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作者 Raphael J. Heffron Kalev Kallemets 《Journal of Energy and Power Engineering》 2012年第4期495-503,共9页
This paper details the prospects for a civil nuclear power station in Estonia. Due to its climate change commitments, Estonia needs a new source of electricity provision. There is little academic literature on Estonia... This paper details the prospects for a civil nuclear power station in Estonia. Due to its climate change commitments, Estonia needs a new source of electricity provision. There is little academic literature on Estonia, and this research builds upon previous work but is more detailed in its analysis with primary data included in the form of interviews with Estonian energy industry experts. All the conditions that have led to nuclear energy being considered as an option are assessed, along with why it represents the most strategic path for Estonia in terms of electricity provision. Through the interview analysis a framework is established and advanced for the successful initiation of a national nuclear power plant project. This research is therefore of high value for small EU countries who intend to consider nuclear energy as an option in their energy mix or have more advanced plans to develop a nuclear program. 展开更多
关键词 NUCLEAR new nuclear building POLICY ELECTRICITY Estonia.
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Determination of Kolmogorov Entropy of Chaotic Attractor Included in One-Dimensional Time Series of Meteorological Data
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作者 严绍瑾 彭永清 王建中 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第2期243-250,共8页
The 1970-1985 day to day averaged pressure dataset of Shanghai and the extension method in phase space are used to calculate the correlation dimension D and the second-order Renyi entropy K2 of the approximation of Ko... The 1970-1985 day to day averaged pressure dataset of Shanghai and the extension method in phase space are used to calculate the correlation dimension D and the second-order Renyi entropy K2 of the approximation of Kolmogorov's entropy, the fractional dimension D = 7.7-7.9 and the positive value K2 - 0.1 are obtained. This shows that the attractor for the short-term weather evolution in the monsoon region of China exhibits a chaotic motion. The estimate of K2 yields a predictable time scale of about ten days. This result is in agreement with that obtained earlier by the dynamic-statistical approach.The effects of the lag time i on the estimate of D and K2 are investigated. The results show that D and K2 are convergent with respect to i. The day to day averaged pressure series used in this paper are treated for the extensive phase space with T = 5, the coordinate components are independent of each other; therefore, the dynamical character quantities of the system are stable and reliable. 展开更多
关键词 Determination of Kolmogorov Entropy of Chaotic Attractor Included in One-Dimensional Time Series of Meteorological Data
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The Structure of Low Frequency Phenomena in the Tropics and Its Interaction with the Extratropics 被引量:1
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作者 Peter J.Webster 董敏 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第1期1-16,共16页
The structure of planetary scale low freonency phenomena in the tropics is studied, and an attempt is made to determine its influence and interactions with phenomena at higher latitudes.In the tropics, it is found tha... The structure of planetary scale low freonency phenomena in the tropics is studied, and an attempt is made to determine its influence and interactions with phenomena at higher latitudes.In the tropics, it is found that the majority of the variance in the zonal wind structure is made up in wave numbers I and 2. During warm events in the Pacific Ocean, when the Southern Oscillation Index is negative, almost all of the variance resides in the gravest mode which undergoes a 40° eastward phase shift. Meanwhile, the second logitudinal mode almost disappears. On the other hand, the meridional wind field possesses maximum amplitude at higher wave numbers. However, near the equator,the amplitude is small with extreme values occurring in the subtropics. The difference in scale and the location of cxtrcma of the meridional and zonal wind components indicate that the tropical atmosphere is responding to two different driving mechanisms.Correlation analyses between variations of the zonal wind at reference points along the equator with variations of component elsewhere show that there are strong logitudinal connections. The strongest correlations between the tropics and higher latitudes exist in the region of the equatorial westerlies. In fact, stronger correlations occur between variations in U anywhere along the equator and the middle latitudes to the north and south of the equatorial westerlies than to the latitudes immediately to the north and south of the reference points. We interpret this 'remote' correlation pattern as indicating a two-stage teleconnection process which emphasizes the importance of the equatorial tropical westerlies of the Pacific Ocean as a 'corridor' of communication between the low and high latitudes. The regionality of the correlations confirms, to some extent, recent theoretical development regarding trapped equatorial modes. Finally, time lagged correlations from plus and minus six months between variations of U and OLR indicate that the interactions between the extratropics and low latitudes possess an organized sequence. The extratropical influence appears to propagate into the tropics followed by an eastward propagation along the equator. Finally, a propagation from the tropics to the extratropics in the upper troposphere occurs in the eastern Pacific Ocean. The time-lagged correlation sequence does not appear to be symmetric about the equator. 展开更多
关键词 In The Structure of Low Frequency Phenomena in the Tropics and Its Interaction with the Extratropics
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2+1维sine-Gordon方程多辛格式的复合构造 被引量:6
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作者 王雨顺 王斌 秦孟兆 《中国科学(A辑)》 CSCD 北大核心 2003年第3期272-281,共10页
以2+1维sine-Gordon方程为例,提出构造多辛算法的一种复合方法,即;独立地辛离散多辛偏微分方程的各个方向,复合这些辛离散格式得到原偏微分方程的多辛算法.通过这种复合方法,可以构造任意阶精度的多辛算法,其中包括一些常用算法.孤立子... 以2+1维sine-Gordon方程为例,提出构造多辛算法的一种复合方法,即;独立地辛离散多辛偏微分方程的各个方向,复合这些辛离散格式得到原偏微分方程的多辛算法.通过这种复合方法,可以构造任意阶精度的多辛算法,其中包括一些常用算法.孤立子的数值模拟试验说明所给出的多辛算法是有效的. 展开更多
关键词 2+1维sine-Gordon方程 多辛格式 多辛算法 复合构造方法 孤子试验 多辛偏微分方程
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