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51.
The use of cellular automata (CA) has for some time been considered among the most appropriate approaches for modeling land‐use changes. Each cell in a traditional CA model has a state that evolves according to transition rules, taking into consideration its own and its neighbors’ states and characteristics. Here, we present a multi‐label CA model in which a cell may simultaneously have more than one state. The model uses a multi‐label learning method—a multi‐label support vector machine, Rank‐SVM—to define the transition rules. The model was used with a multi‐label land‐use dataset for Luxembourg, built from vector‐based land‐use data using a method presented here. The proposed multi‐label CA model showed promising performance in terms of its ability to capture and model the details and complexities of changes in land‐use patterns. Applied to historical land use data, the proposed model estimated the land use change with an accuracy of 87.2% exact matching and 98.84% when including cells with a misclassification of a single label, which is comparably better than a classical multi‐class model that achieved 83.6%. The multi‐label cellular automata outperformed a model combining CA and artificial neural networks. All model goodness‐of‐fit comparisons were quantified using various performance metrics for predictive models. 相似文献
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Salim Heddam 《Environmental Earth Sciences》2016,75(3):261
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Mineralogical and geochemical characterization of listwaenite from the Semail Ophiolite, Oman 总被引：2，自引：0，他引：2
Sobhi Nasir Abdul Razak Al Sayigh Abdulrahman Al Harthy Salah Al-Khirbash Omar Al-Jaaidi Abdullah Musllam Ali Al-Mishwat Salim Al-Bu'saidi 《Chemie der Erde / Geochemistry》2007,67(3):213-228
The late Cretaceous-lower Tertiary hydrothermal alteration of serpentinized peridotite in the Semail ophiolite has formed two distinct types of listwaenite. Type I is characterized by the presence of calcite (Type IA) or dolomite (Type IB)+fuchsite±spinel. Type II is dominated by silicate minerals (quartz, chlorite, fuchsite)±calcite+dolomite±magnetite±apatite±plagioclase. Most listwaenites occur as veins along thrust fault zones within the ophiolite mélange. High Cr and Ni contents, abundant occurrence of Cr-spinel within a matrix of red-brown ferruginous carbonates within a micro-vein network of goethite, and the relics of mesh texture indicate an ultramafic protolith. Type I and II listwaenites represent different stages of hydrothermal alteration. The mineralogical and chemical distinctions of both types are the response to the extent of the reactions between the protoliths and the solutions leading to different stages of metasomatic replacement. The hydrothermal fluids involved in the formation of Type I listwaenite were enriched in Ca, Mg, and CO2, whereas Type II listwaenite bodies were formed from a hydrothermal fluid enriched in SiO2. REE and trace elements in both listwaenite types were extracted in part from adjoining peridotite. No Au anomaly in the study areas has been detected. 相似文献
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Haidar Salim Anan 《Arabian Journal of Geosciences》2017,10(19):431
Three subspecies belong to middle-late Maastrichtian Bolivinoides draco group (B. draco aegyptiacus, B. d. draco, and B. d. dorreeni) are described of which one is new: Bolivinoides draco aegyptiacus from Abu Zenima section, west central Sinai, Egypt. This new subspecies differs from the other Bolivinoidid taxa in possessing well-developed two divergent medial longitudinal ribs along the smooth test surface, with another one rib in the central part between them. In this study, the early Maastrichtian B. miliaris is not related to this group. The other evolutionary trends are also distinguished and the paleogeographic distributions of Bolivinoides members in the Middle East are presented. 相似文献
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Aerosol and water vapour are very important element in the Earth’s climate system which has direct role in the Earth’s radiation budget. In this paper the seasonality, latitudinal distribution and the relationship of aerosol optical thickness (AOD) and water vapour (WV) using MODIS Level 3 monthly data from 2001 to 2008 are analysed. The analysis shows that AOD (0.55 μm) values reach maximum during southwest monsoon and remain minimum during northeast monsoon period. The Equatorial Indian Ocean shows minimum AOD (0.115 to 0.153) throughout the year compared to Arabian Sea (0.208 to 0.613) and Bay of Bengal (0.214 to 0.351). Arabian Sea shows high variation and maximum value of AOD compared to Bay of Bengal and Equatorial Indian Ocean. During southwest monsoon WV over Bay of Bengal was found higher in concentration compared to Arabian Sea and Equitorial Indian Ocean throughout the study period. Comparison between Arabian Sea (2.98 cm to 5.07 cm) and Bay of Bengal (3.49 cm to 5.94 cm) shows that WV concentration is less in Arabian Sea throughout the year. The analysis of correlation between WV and AOD was found to be inconsistent. However, AOD and WV shows a strong positive correlation for whole year (Mean R2 =0.90) in the Equitorial Indian Ocean region except in the months of January, February and March. In general, the correlation between WV and AOD is found to be strongly positive for oceanic aerosol (sea salt) in low water vapour condition. 相似文献
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Chris Flynn J. Sommer-Larsen B. Fuchs David S. Graff Samir Salim 《Monthly notices of the Royal Astronomical Society》2001,322(3):553-560
Ibata et al. have recently discovered very faint, moving objects in the Hubble Deep Field (HDF). The number, apparent magnitudes and proper motions of these objects are consistent with old white dwarfs making up part of the Galactic dark halo. We review a number of ground-based proper motion surveys in which nearby dark-halo white dwarfs might be present, if they have the colours and absolute magnitudes proposed. No such objects have been found, whereas we argue here that several times more would be expected than in the HDF. We conclude that it is unlikely that hydrogen-atmosphere white dwarfs make up a significant fraction of the Galactic dark matter. No limits can be placed as yet on helium-atmosphere dwarfs from optical searches. 相似文献
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Seifollahi Mehran Abbasi Salim Abraham John Norouzi Reza Daneshfaraz Rasoul Lotfollahi-Yaghin Mohammad-Ali Alkan Ahmet 《Geotechnical and Geological Engineering》2022,40(11):5481-5496
Geotechnical and Geological Engineering - The aim of this study is to optimize the geometric dimensions of the Koyna concrete weight dam with and without seismic forces using the grasshopper... 相似文献
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Geotectonics - The Early Oligocene alkalibasalts exposed in the Central Toveireh area located in the southwest of Jandaq city in Isfahan Province (Iran) and northwest of the Central-East Iranian... 相似文献
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Wahyudi A’an J. Rahmawati Susi Irawan Andri Hadiyanto Hadiyanto Prayudha Bayu Hafizt Muhammad Afdal Afdal Adi Novi S. Rustam Agustin Hernawan Udhi. E. Rahayu Yusmiana P. Iswari Marindah Y. Supriyadi Indarto H. Solihudin Tubagus Ati Restu Nur Afi Kepel Terry L. Kusumaningtyas Mariska A. Daulat August Salim Hadiwijaya L. Sudirman Nasir Suryono Devi D. Kiswara Wawan 《Ocean Science Journal》2020,55(1):85-97
Ocean Science Journal - Seagrass meadows provide critical ecosystem services for coastal areas, e.g., as nursery habitats for various fish species, help with water filtration of suspended sediment,... 相似文献